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Wednesday, 18 January 2012

ASP TUTORIALS

What Are Active Server Pages?

Active Server Pages (ASPs) are Web pages that contain server-side scripts in addition to the usual mixture of text and HTML (Hypertext Markup Language) tags. Server-side scripts are special commands you put in Web pages that are processed before the pages are sent from your Personal Web Server to the Web browser of someone who's visiting your Web site. . When you type a URL in the Address box or click a link on a Web page, you're asking a Web hosting server on a computer somewhere to send a file to the Web browser (sometimes called a "client") on your computer. If that file is a normal HTML file, it looks exactly the same when your Web browser receives it as it did before the Web server sent it. After receiving the file, your Web browser displays its contents as a combination of text, images, and sounds. In the case of an Active Server Page, the process is similar, except there's an extra processing step that takes place just before the Web server sends the file. Before the Web server sends the Active Server Page to the Web browser, it runs all server-side scripts contained in the page. Some of these scripts display the current date, time, and other information. Others process information the user has just typed into a form, such as a page in the Web site's guestbook.
To distinguish them from normal HTML pages, Active Server Pages are given the ".asp" extension.

 

How Does ASP Differ from HTML?

  • When a browser requests an HTML file, the server returns the file
  • When a browser requests an ASP file, IIS passes the request to the ASP engine. The ASP engine reads the ASP file, line by line, and executes the scripts in the file. Finally, the ASP file is returned to the browser as plain HTML

What can ASP do for you?

  • Dynamically edit, change, or add any content of a Web page
  • Respond to user queries or data submitted from HTML forms
  • Access any data or databases and return the results to a browser
  • Customize a Web page to make it more useful for individual users
  • The advantages of using ASP instead of CGI and Perl, are those of simplicity and speed
  • Provide security - since ASP code cannot be viewed from the browser
  • Clever ASP programming can minimize the network traffic

 

Your Windows PC as a Web Server

  • Your own PC can act as a web server if you install IIS or PWS
  • IIS or PWS turns your computer into a web server
  • Microsoft IIS and PWS are free web server components

IIS - Internet Information Server

IIS is a set of Internet-based services for servers created by Microsoft for use with Microsoft Windows.
IIS comes with Windows 2000, XP, Vista, and Windows 7. It is also available for Windows NT.
IIS is easy to install and ideal for developing and testing web applications.

PWS - Personal Web Server

PWS is for older Windows system like Windows 95, 98, and NT.
PWS is easy to install and can be used for developing and testing web applications including ASP.
We don't recommend running PWS for anything else than training. It is outdated and has security issues.

Windows Web Server Versions

  • Windows 7 (all editions) come with IIS 7.5
  • Windows Vista Business, Enterprise and Ultimate come with IIS 7
  • Windows Vista Home Premium comes with IIS 7
  • Windows Vista Home Edition does not support PWS or IIS
  • Windows XP Professional comes with IIS 5.1
  • Windows XP Home Edition does not support IIS or PWS
  • Windows 2000 Professional comes with IIS 5.0
  • Windows NT Professional comes with IIS 3 and also supports IIS 4
  • Windows NT Workstation supports PWS and IIS 3
  • Windows ME does not support PWS or IIS
  • Windows 98 comes with PWS
  • Windows 95 supports PWS

How to Install IIS on Windows 7 and Windows Vista

Follow these steps to install IIS:
  1. Open the Control Panel from the Start menu
  2. Double-click Programs and Features
  3. Click "Turn Windows features on or off" (a link to the left)
  4. Select the check box for Internet Information Services (IIS), and click OK
After you have installed IIS, make sure you install all patches for bugs and security problems. (Run Windows Update).

How to Install IIS on Windows XP and Windows 2000

Follow these steps to install IIS:
  1. On the Start menu, click Settings and select Control Panel
  2. Double-click Add or Remove Programs
  3. Click Add/Remove Windows Components
  4. Click Internet Information Services (IIS)
  5. Click Details
  6. Select the check box for World Wide Web Service, and click OK
  7. In Windows Component selection, click Next to install IIS
After you have installed IIS, make sure you install all patches for bugs and security problems. (Run Windows Update).

Test Your Web

After you have installed IIS or PWS follow these steps:
  1. Look for a new folder called Inetpub on your hard drive
  2. Open the Inetpub folder, and find a folder named wwwroot
  3. Create a new folder, like "MyWeb", under wwwroot
  4. Write some ASP code and save the file as "test1.asp" in the new folder
  5. Make sure your Web server is running (see below)
  6. Open your browser and type "http://localhost/MyWeb/test1.asp", to view your first web page
Note: Look for the IIS (or PWS) symbol in your start menu or task bar. The program has functions for starting and stopping the web server, disable and enable ASP, and much more.

How to install PWS on Windows 95, 98, and Windows NT

For Windows 98: Open the Add-ons folder on your Windows CD, find the PWS folder and run setup.exe to install PWS.
For Windows 95 or Windows NT: Download "Windows NT 4.0 Option Pack" from Microsoft, and install PWS.
Test your web as described above.

How to install IIS on Windows Server 2003

  1. When you start the Windows Server 2003, you should see the Manage Your Server wizard
  2. If the wizard is not displayed, go to Administrative Tools, and select Manage Your Server
  3. In the wizard, click Add or Remove a Role, click Next
  4. Select Custom Configuration, click Next
  5. Select Application Server role, click Next
  6. Select Enable ASP.NET, click Next
  7. Now, the wizard may ask for the Server 2003 CD. Insert the CD and let it run until it is finished, then click the Finish button
  8. The wizard should now show the Application Server role installed
  9. Click on Manage This Application Server to bring up the Application Server Management Console (MMC)
  10. Expand the Internet Information Services (IIS) Manager, then expand your server, and then the Web Sites folder
  11. You should see the Default Web Site, and it should not say (Stopped)
  12. IIS is running!
  13. In the Internet Information Services (IIS) Manager click on the Web Service Extensions folder
  14. Here you will see that Active Server Pages are Prohibited (this is the default configuration of IIS 6)
  15. Highlight Active Server Pages and click the Allow button
  16. ASP is now active!

 

What Can You Do with Active Server Pages?

There are many things you can do with Active Server Pages.
  • You can display date, time, and other information in different ways.
  • You can make a survey form and ask people who visit your site to fill it out, send emails, save the information to a file, etc

What Do Active Server Pages Look Like?

The appearance of an Active Server Page depends on who or what is viewing it. To the Web browser that receives it, an Active Server Page looks just like a normal HTML page. If a visitor to your Web site views the source code of an Active Server Page, that's what they see: a normal HTML page. However, the file located in the server  looks very different. In addition to text and HTML tags, you also see server-side scripts. This is what the Active Server Page looks like to the Web server before it is processed and sent in response to a request.

What Do Server-Side Scripts Look Like?

Server-side scripts look a lot like HTML tags. However, instead of starting and ending with lesser-than ( < ) and greater-than ( > ) brackets, they typically start with <% and end with %>. The <% is called an opening tag, and the %> is called a closing tag. In between these tags are the server-side scripts. You can insert server-side scripts anywhere in your Web page--even inside HTML tags.

Displaying the Current Date and Time

The date and time described in this section are those that are on the server.

Date

To display the current date by itself in a Web page, type: 
<% =date %>
at the point where you want it to appear. When you view the page in your browser, you should see something like this: Thu, Jan 23, 1997
Note: Even though "=date" is a short script, it's actually made up of two parts. The "date" part tells the server, "Get me the date." The equal sign (=) tells the server to display the date in the Web page. If you typed just: 
<% date %>
the server would get the current date from your system, but that's all. It wouldn't display it. There are times when it makes sense to use an ASP function without the equal sign.

Time

To display the current time by itself, type: 
<% =time %>
where you want it to appear. When you view the page, you should see something like this: 4:19:46 PM

Now (Date and Time)

To display the current date and time, type: 
<% =now %>
where you want them to appear. When you view the page, you should see something like this: 1/23/97 4:19:46 PM

Changing the Way Date and Time are Displayed

You can also use Active Server Pages (ASP) functions to customize the way the current date and time are displayed on your Web page. To do this, use the now function together with the following formatting functions.

Month and Monthname

To display the number of the current month in a Web page, type: 
<% =month(now) %>
where you want it to appear. When you view the page in your browser, you'll see a 1 if the current month is January, 2 if it's February, and so on. To display the name of the current month, type: 
<% =monthname(month(now)) %>
where you want it to appear.

Day

To display the day of the current month, type: 
<% =day(now) %>
where you want it to appear. When you view the page, you'll see a number between 1 and 31.

Year

To display the current year, type: 
<% =year(now) %>
where you want it to appear.

Example

Suppose you wanted to display today's date as day/month/year instead of month/day/year. To do so, you would use the day, month, and year ASP functions together, by typing: 
<% =day(now) %>/<% =month(now) %>/<% =year(now) %>
When you viewed the page, you would see something like this: 23/1/1997
Later we'll see how you can change this so only the last two digits of the year are displayed, like this:
23/1/97

Weekday and Weekdayname

To display the day of the week as a number from 1 to 7 in a Web page, type: 
<% =weekday(now) %>
where you want it to appear. When you view the page in Internet Explorer, you'll see a 1 if today is Sunday, 2 if it's Monday, and so on. To display the day of the week by name, type: 
<% =weekdayname(weekday(now)) %>
where you want it to appear.

Hour, Minute, and Second

To display just the hour part of the current time, type: 
<% =hour(now) %>
where you want it to appear. The hour function is based on a 24-hour clock. When you view the page, you'll see a number between 0 and 23. To display just the minutes part of the current time, type: 
<% =minute(now) %>
where you want it to appear. When you view the page, you'll see a number between 0 and 59. To display just the seconds part of the current time, type: 
<% =second(now) %>
where you want it to appear. When you view the page, you'll see a number between 0 and 59.

Example

Try typing this into a Web page: 
The time is <% =time %>. That means it's <% =minute(now) %> 
minutes past <% =hour(now) %> o'clock.
When you view the page in Internet Explorer, you should see something like this: The time is 1:36:05 PM. That means it's 36 minutes past 13 o'clock.
Remember, the hour function is based on a 24-hour clock. Later we'll see how to convert from the 24-hour clock to a 12-hour clock.

Timevalue

You probably won't ever use the timevalue function. It takes the different ways you can write the time, such as "2:24PM" and "14:24," and returns them in this format: "2:24:00 PM." This can be useful if you're using a function that needs to be given the time in that exact format.

Example

Earlier in this section we saw how you can use the hour, minute, and second functions to break up the time into hours, minutes, and seconds. With the timevalue function, you can put them back together. Type this into a Web page: 
When it's 23 minutes and 5 seconds past 4 o'clock in the afternoon,
that means it's <% =timevalue("16:23:05") %>.
This is the same as <% =timevalue("4:23:05PM") %>
or <% =timevalue("16:23:05PM") %>.
Make sure you type "16:23:05PM" and not "16:23:05 PM." The "05" and the "PM." should be run together, not separated by a space. When you view the page in Internet Explorer, you should see: When it's 23 minutes and 5 seconds past 4 o'clock in the afternoon, that means it's 4:23:05 PM. This is the same as 4:23:05 PM or 4:23:05 PM.

Displaying Text

len

The len function tells you how many characters are in a word or sequence of words. (The name "len" is an abbreviation of "length.") All characters are counted, including the space character. For example, to find the length of the sentence "The cat is on the mat," type this into a Web page: 
There are <% =len("The cat is on the mat.") %> characters in 
"The cat is on the mat."
When you view the page in Internet Explorer, you should see this: There are 22 characters in "The cat is on the mat."

left

You can use the left function to look at the first few characters of a word or sequence of words. For example, to find the first character of "Frankenstein," type this into a Web page: 
"Frankenstein" begins with the letter <% =left("Frankenstein", 1) %>.
When you view the page, you should see this: "Frankenstein" begins with the letter F.

right

To look at the last few characters of a word or sequence of words, use the right function. For example, to find the last three letters of "Wednesday," type this into a Web page: 
The last three letters of "Wednesday" are: <% =right("Wednesday", 3) %>.
When you view this page, you should see this: The last three letters of "Wednesday" are: day.

Example

What if you wanted to take a few letters from the middle of something? How would you specify exactly where in the middle you wanted to be? For example, how would you take out just the "apple" part of the word "pineapples"? You could start with the fifth character from the left and then stop at the second character from the right. Or you could do it the following way.
Try typing this into a Web page: 
<% =right("pineapples", 6) %> <% =left(right("pineapples", 6), 5) %>
This line takes the last six letters of the word "pineapples," which make up the word "apples." Then it takes the first five letters of the word "apples," which make up the word "apple." When you view this page in Internet Explorer, you should see this:
apples apple
Then try typing this into a Web page: 
<% =left("pineapples", 9) %> <% =right(left("pineapples", 9), 5) %>
This line takes the first nine letters of the word "pineapples," which make up the word "pineapple." Then it takes the last five letters of the word "pineapple," which make up the word "apple." When you view this page, you should see this:
pineapple apple

Cool Things You Can Do with Date, Time, and Text

Here are some examples of interesting things you can do with date, time, and text functions.

Link of the Day

What if you wanted to have a link that pointed to a different page every day of the week? Here's how you can do that. First, choose the pages (HTML files) on your Web site that you want your link to point to. Name them "Sunday.htm," "Monday.htm," and so on. (If you don't have seven different HTML files, you can copy some of the files or make aliases on your Macintosh to them. The important thing is that there has to be one file or alias for every day of the week.) To make the link, type 
<a href= <% =weekdayname(weekday(now)) %>.htm>Link of the Day</a>
where you want it to appear. When you click this link in Internet Explorer, it will take you to today's page.

Another Way to Display Today's Date

Earlier we saw how to change the date display from month/day/year to day/month/year like this: 23/1/1997
We can also change the date display so only the last two digits of the year are included. To do this, type 
<% =day(now) %>/<% =month(now) %>/<% =Right((year(now)), 2) %>
Now when you view the page, you should see something like this: 23/1/97

Another Way to Display the Time

In an earlier example, we wrote a server-side script to display the current time in words, such as: "The time is 36 minutes and 5 seconds past 13 o'clock." This script used the ASP hour function, which returns just the hour part of the current time, based on a 24-hour clock. In this example, we'll see how to change 24-hour clock times such as "13 o'clock" to 12-hour clock times ("1 o'clock PM"). To do this, we'll need to make the server-side script that uses the hour function a little more complicated. Instead of 
<% =hour(now) %> o'clock
we'll need to write a script that looks at the hour and does one of the following:
  • If the hour is 0 (zero), the script displays "midnight."
  • If the hour is 12, the script displays "noon."
  • If the hour is between 1 and 11, the script doesn't change it, but it displays "AM" after "o'clock."
  • If the hour is between 13 and 23, the script subtracts 12 (to make it a number between 1 and 11) and displays "PM" after "o'clock."
The script is shown below. It isn't written quite the way a programmer would write it, but it works, and it's fairly easy to understand, since it follows the items in the bulleted list above exactly. 
The hour is 
<% if hour(now) = 0 then %>
   midnight.
<% end if 
   if hour(now) = 12 then %>
  noon.
<% end if 
   if (hour(now) >= 1) and (hour(now) <= 11) then %>
    <% =hour(now) %> o'clock AM.
<% end if 
   if (hour(now) >= 13) and (hour(now) <= 23) then %>
    <% =hour(now) - 12 %> o'clock PM.
<% end if %>
If you type (or better yet, cut-and-paste) this script in a Web page, when you view the page, you should see something like this: The hour is 4 o'clock PM.

Using Variables, and Forms in Active Server Pages

Forms are a convenient way to communicate with visitors to your Web site. Using forms, you can create a survey form and ask visitors to fill it out. When they fill out the form, you can process the results automatically. With forms, there are two steps: first you create the form, and then you process it. To create a form for an Active Server Page, just create a standard HTML form.
To try out this example, create an HTML file ("form_response.html") and cut-and-paste the following text into it.
 
form_response.html
<html>
<head><title>Asking for information</title></head>
<body>
<form method="post" action="form_response.asp">
Your name: <input type="text" name="name" size="20"><BR>
Your email: <input type="password" name="email" size="15"><BR>
<input type="Submit" value="Submit">
</form>
</body>
</html>
Active Server Pages provide a mechanism for processing forms that, unlike CGI scripting, doesn't involve serious programming: the Request.Form.
Considering the form above, we may create the file bellow and get a response.
 
form_response.asp
<html>
<head><title>Responding to a form</title></head>
<body>
Your name is <% =Request.Form("name") %> <BR>
Your email is <% =Request.Form("email") %>
</body>
</html>
To display the contents of each field in the form, type: 
<% =Request.Form(fieldname) %>
where fieldname is the name of the field.
 

Creating a Variable

You'll probably want to do more with your forms than display their contents in a Web page. For example, based on the contents of the form, you may want to create a variable and insert that variable in different places of your response page. You may need to create a variable. To do that, just make up a name and set it equal to the contents of the field. For example, if you have a field called "CatName" in your form, you can save it into a variable called "TheName" by typing: 
<% TheName = Request.Form("CatName") %>
If you want to display "VisitorName" several times within a text you only need to include the variable in the text. For example: My cat´s name is <% =TheName %>. Do you want to see <% =TheName %>?.

Example

The form in this example asks users to introduce their names and their favorite color: red, blue, or green. When the form is received, the server responds displaying these data.
 
nameandcolor.html
<html>
<head><title>Name and Color</title></head>
<body>
<FORM ACTION="nameandcolor.asp" METHOD=POST>
Let me know your Name and Favorite Color:
<P>YOUR NAME: 
<INPUT TYPE="TEXT" NAME="YOURNAME" SIZE=20>
<P>COLOR: 
<INPUT TYPE="RADIO" NAME="COLOR" VALUE="1" CHECKED>Red
<INPUT TYPE="RADIO" NAME="COLOR" VALUE="2">Green
<INPUT TYPE="RADIO" NAME="COLOR" VALUE="3">Blue
<P>
<INPUT TYPE="SUBMIT" VALUE="OK">
</FORM>
</body>
</html>
Now, create an ASP file ("nameandcolor.asp") and cut-and-paste the following text into it.
 
nameandcolor.asp
<html>
<head><title>Name and Color</title></head>
<body>
<% TheName = Request.Form("YOURNAME") %>
<% colornumber = Request.Form("COLOR") %>
Hi, <% =Thename %>.<BR>
I know your favorite color is
<% if colornumber = "1" then %>
red
<% end if %>
<% if colornumber = "2" then %>
green
<% end if %>
<% if colornumber = "3" then %>
blue
<% end if %>.
</body>
</html>

If....Then...Else
The If....Then...Else instructions sequence is very similar to the one we may find in different kind of scripting languages. Let's check an example.
 
<% 
AA="water" If AA="water" Then
 response.write ("I want to drink water")
Else
 response.write ("I want to drink milk")
End If
%>
We may use it this way:
<%  AA="water"
If AA="water" Then %>        I want to drink water
<% Else %>
       I want to drink milk
<% End If %>
In both cases we have checked a condition (AA="water"), and we have get a positive instruction (to write the sentence "I want to drink water"). We are allowed to execute any kind of instructions (including  If....then....Else) and as many instructions as we want .
 
For....Next
This instructions is also similar in different programming languages. Let's see a typical example.
 
example.as
I want to say "Hello" 10 times<BR>
<% For mynumber = 1 to 10 %>
<% =mynumber %> Hello<BR>
<% Next %>
END
In this case we have defined a variable ("mynumber") and using the For...Next instruction we have repeated 10 times line 4. Similarly to If....Then....Else instruction, we are allowed to execute any kind of instructions and as many of them as we want .
The For...Next instruction allows to define the value of the increment.
 
<% For mynumber = 1 to 20 STEP 2
response.write("Hello<BR>")
Next %>
<% For mynumber = 20 to 1 STEP -2
response.write("Hello<BR>")
Next %>
In both cases we will get the same response ("Hello" 10 times). The increment may be positive or negative as shown in the example.

Do While...Loop
Again, we will define a condition and one or more instructions:
 
<% 
mynumber=0
Do While mynumber<10     response.write("Hello<HR>")
    mynumber=mynumber+1
Loop
%>
In this example the condition is "mynumber<10" and the instructions defines a response text and an increment of the variable "mynumber". In the example, mynumber will be increased until it gets a value of 10. Then the loop will be abandon. Several instruction may be used within the loop.
Do Until....Loop
Quite similar to the previous one, it also includes a condition and one or more instructions:
 
<%
mynumber=0
Do Until mynumber=10     response.write("Hello<HR>")
    mynumber=mynumber+1
Loop
%>
In this example the condition is "mynumber=10", so mynumber will increased until it is equal to 10, and then the loop will be abandon.
Let's see an example using this Do Until...Loop:
 
<%
myfirstnumber=0
mysecondnumber=0 Do Until myfirstnumber=15
     Do Until mysecondnumber=15
              response.write("X")
              mysecondnumber=mysecondnumber+1
     Loop
     Response.write ("<BR>")
     myfirstnumber=myfirstnumber+1
     mysecondnumber=myfirstnumber
Loop
Response.write ("END")
%>
The result of the script is this one:
 
XXXXXXXXXXXXXXX
XXXXXXXXXXXXXX
XXXXXXXXXXXXX
XXXXXXXXXXXX
XXXXXXXXXXX
XXXXXXXXXX
XXXXXXXXX
XXXXXXXX
XXXXXXX
XXXXXX
XXXXX
XXXX
XXX
XX
X
END
Select Case....End Select
This is a very useful instruction in case we want to check different values for variable. Lets check an example:
 
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 <%
mynumber=3
Select Case mynumber
   Case 1
       Response.write ("Number 1")
   Case 2
       Response.write ("Number 2")
   Case 3
       Response.write ("Number 3")
   Case 4
       Response.write ("Number 4")
   Case 5
       Response.write ("Number 5")
   Case Else
       Response write ("Mynumber is higher than 5")
End Select
%>
In this example above, we have defined mynumber  as 3, so they are executed the instructions following line 8 (in this case only one instruction is executed, but they may be several instructions). Case Else is not necessary.
Let's try a second example:
 
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 <%
username=request.form("username")
Select Case username
   Case "Peter"
       Response.write ("Hello, Peter")
   Case "John"
       Response.write ("Hello, John")
   Case "Joe"
       Response.write ("Hi, Joe")
   Case Else
       Response write ("I do not know you")
End Select
%>
Let's see a different example:
 
backgroundform.html
<html>
<head><title>Chose background color</title></head>
<form action="backgroundresponse.asp" method="post">
Which color do you prefer to use as your background?
<BR>
<input type="radio" name="kindofcolor" value="defined" checked>
Defined color
<select name="definedcolor">
<option value="#FFFFFF">White</option>
<option value="#FF0000">Red</option>
<option value="#00FF00">Green</option>
<option value="#0000FF">Blue</option>
</select>
<BR>
<input type="radio" name="kindofcolor" value="custom">
Custom color
<input type="text" size="8" name="mycolor"></input>
<BR><input type="Submit" value="Submit"></input>
</form>
</body>
</html>
backgroundresponse.asp
<%
kindofcolor=Request.form("kindofcolor") Select Case kindofcolor
   case "defined"
    colorofbackground=Request.form("definedcolor")
       Select Case colorofbackground
                 case "#FFFFFF"
                      texttoshow="White"
                 case "#FF0000"
                      texttoshow="Red"
                 case "#00FF00"
                      texttoshow="Green"
                 case "#0000FF"
                      texttoshow="Blue"
        End select
   case "custom"
        colorofbackground=Request.form("mycolor")
        texttoshow="Custon color"
End select
%>
<html>
<head><title>Chose background color</title></head>
<body bgcolor="<% =colorofbackground %>">
<center>
<H1><% =texttoshow %></H1>
</center>
</form>
</body>
</html>
 
Subroutines
Subroutines have the same utility in ASP as it has in other languages.
In the next two examples, we have asked our visitors his name, and depending on that answer a different response is sent to the client. The response will be the same in both cases, but in the second one subroutines are used. The use of subroutines may be very useful when there are a lot of instructions to be perform within a subroutine. This way it will allow us to simplify the structure of our script.
Example 1
<% 
TheName=request.form("name) if TheName="John" then
response.write ("Hi, John. How are you?")
response.write ("<br>Did you know I got married last month?")
else
response.write ("Hi. How are you?")
end if
%>
Example 2
<% 
TheName=request.form("name) if TheName="John" then
ResponseToJohn()
else
ResponseToUnknown()
end if
Sub ResponseToJohn()
response.write ("Hi, John. How are you?")
response.write ("<br>Did you know I got married last month?")
End Sub
Sub ResponseToUnknown()
response.write ("Hi. How are you?")
End Sub
%>
In order to call a subroutine, we will use this kind of code:
Whatever()
Where Whatever is the name of the subroutine (it is recommended to use a very descriptive name of the task we want to perform within the subroutine to make it easier to understand the script). We may also provide information to the subroutine in order to perform the specified task. The data will be provided this way:
Whatever(data1, data2 ... dataN)
In the following example we will provide different  data to a unique subroutine depending on the Name of the person provided throw a form:
Example 3
<% 
TheName=request.form("name) if TheName="John" then
ResponseToVisitor(35,Sue,New York)
else
   if TheName="Peter" then
   ResponseToVisitor(33,Sally,Los Angeles)
   else
   response.write("Who are you?")
   end if
end if
Sub ResponseToVisitor(AA,BB,CC)
response.write ("I know your are" & AA & "years old, ")
response.write ("you are married to" & BB & ", and")
response.write ("you are living in " & CC)
End Sub
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In line 14 it is specified AA is the first variable to be get, BB the second one, and CC the third one. The values for the three variables are provided in the same order in line 5 or line 8.
The example above also shows subroutines are very useful to avoid repeating a specific number of tasks several times within the script, so that the script looks more organized and it is smaller.
 
Include/virtual
Server Site includes or SSI is a very simple programing language (see a small tutorial) but it also has a very limited number of instructions. We will consider only one option SSI allows us to use within our asp scripts: include/virtual.
In the next example we will use the include option of SSI in a our asp script (response.asp). This command allows as to add a set of instructions from different files (file1.txt and file2.txt bellow) and execute them.
Example 4
response.asp
<%
TheName=request.form("name) if TheName="John" then
   %>
   <!--#include virtual="/file1.html" -->
   <% else %>
   <!--#include virtual="/file2.asp" -->
   <%
end if %>
File1.html
Hi, John.<br>
I know your are 31 years old, you are married to Sue, and you are living in New York.
File2.asp
<%
for i=1 to 3
response.write(Thename & "...<BR>")
next
response.write("Who are you?")
%>

  In this case, if the name of the person who is visiting our page is John, then we will respond with file1.html. If not, then we will execute some asp instructions from file2.asp.
The include file must be a text file (.txt, .html, .htm, .shtml, .asp...). Although we have used file1.html and file2.asp, the script will work exactly in the same way with file1.txt and file2.txt (changing the name of the files would have no effect).
 
By using SSI and asp we may also get a secret page:
 
secret_page.asp
<%
UserName=request.form ("username")
Password=request.form("password")
if UserName="myusername" and Password="mypassword" then
%>
<!--#include virtual="/cgi-bin/secret_info.txt" -->
<% else %>
<Form Action=secretpage.asp method=post>
Username:  <input type=text name=username size=15><BR>
Password:  <input type=text name=password size=15><BR>
<input type=Submit Value=Send>
</form>
<% end if %>
secret_info.txt
This is my secret information:<BR>
My name is John.<BR>
My surname is Smith.<BR>
<BR>End of secret information.
In this case it is convenient to save secret_info.txt file in the cgi-bin directory (the .txt file is not accessible by visitors from this directory, but it will be accessible from our top directory).

In this page we will learn how to keep information from the user in our server (Session method) and how to share information between users (Application method). This is only a basic tutorial for beginners, so only basic features will be described.
The Session method
The first time a user accesses to a our pages some connections and disconnections took place. During this process the server and the client will interchange information to identify each other. Due to this exchange of information our server will be able to identify a specific user and this information may be use to assign specific information to each specific client. This relationship between computers is call a session. During the time a session is active, it is possible to assign information to a specific client by using Session method. We will use an example to explain this method:
Let's suppose we want to allow specific user to access the information on our site or directory and we want to show a username in all pages visited by the user. In this case we may use the Session method.
In this example, we will ask the username of the person in our index.asp page
 
respondtoforms.asp
<% IF Request.form="" THEN %> <html>
<title>Our private pages</title>
<body>
In order to access this pages fill the form below:<BR>
<form method="post" action="index.asp">
Username: <input type="text" name="username" size="20"><BR>
Password: <input type="password" name="password" size="15"><BR>
<input type="Submit" value="Submit">
</form>
</body>
</html>
<% ELSE %>
<%
IF Request.form("username")="Joe" AND Request.form("password")="please" THEN
%>
<%
Session("permission")="YES"
Session("username")="Joe"
%>
<html>
<title>Our private pages</title>
<body>
Hi <% =Session("username") %>, you are allow to see these pages: <BR>
<A HREF="page1.asp">Page 1</A><BR>
<A HREF="page2.asp">Page 2</A>
</body>
</html>
<% ELSE %>
Error in username or password
<% END IF %>
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Let's explain how this page works:
In line 1 it is checked whether information is submitted throw a form. If the answer is negative (Request.form=""), a form is displayed asking for username and password.
After filling the form and submitting it, as Request.form is not "" and the script will jump to line 15. In line 17  they are checked the username and password. If user name is "Joe" and Password is "please", then two variables are set for the client (lines 21-22):
  Session("permission")="YES"
  Session("username")="Joe"
These variables will be kept in the server during the time the session is active (normally it will expire after 20 minutes without contact).
Finally, if username and password are correct, a response page with links is send to the client with the name of the user in the top. In this example, if the username or password are incorrect the response page will include the text in line 38.
Now, let's suppose the user clicks in the link "Page 1" (page1.asp). The code of page1.asp will be the following one:
 
page1.asp
<% IF Session("permission")="YES" THEN %> <html>
<title>Page 1</title>
<body>
Hi <% =Session("username") %>, welcome to Page 1 <BR>
This page is empty at the moment, but it will be very interesting in the next future
</body>
</html>
<% ELSE %>
You are not allowed to access this page
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In line 1 it is check whether the value for Session("permission") is "YES". If the answer is positive a page with information is send to the client. If the answer is negative, the text in line 15 is send.
NOTES:
  • Session method is suitable for sites with a limited number of visitors. For sites with a bigger number of visitors it is preferable to keep the information in the clients computer (by using cookies).
  • To create more variables associated to a specific client we must substitute the text between brackets in Session("text").
  • The corresponding security features in the client's browser must be enable.
The Application method With Session method we have defined a value for Session("whatever")="Joe", but this information can not be share between visitors (Session("whatever") has a unique value for each visitor). To allow sharing information Application method is used.
For a better understanding of this method we will create a counter which will be shown in the same page. In order to make it work, copy the code below to your server:
 
counter.asp
<%
Aplication.Lock
Application("pagevisits")=Application("pagevisits")+1
Application.Unlock
%> <html>
<title>Page under construction</title>
<body>
Under construction<BR><BR>
Page views: <% =Application("pagevisits") %>
</body>
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In the first part of this code, as Application method is shared between different clients, it is necessary to prevent other clients from modifying the information in  Application("pagevisits"). Application.Lock will avoid that by stopping the information to be shared, and Application.Unlock will allow the information to be shared again. Line 3 increases the value for the counter.
Finally a html code is send to the client, including the value of the counter.
NOTES:
  • The information save as Application("whatever") as shown in this tutorial is lost each time the server is restarted.
Session and Application method has been used to create a simple chat script (copy and paste the code to your site and it will work immediately.

The Dictionary object
 
In order to learn how Dictionary object works we will create a small script which will translate number 1 to 10 from English to Spanish.
 
 
translate.asp
<%
SET MyDictionary=CreateObject("Scripting.Dictionary")
MyDictionary.Add "one","uno"
MyDictionary.Add "two","dos"
MyDictionary.Add "three","tres"
MyDictionary.Add "four","cuatro"
MyDictionary.Add "five","cinco"
MyDictionary.Add "six","seis"
MyDictionary.Add "seven","siete"
MyDictionary.Add "eight","ocho"
MyDictionary.Add "nine","nueve"
MyDictionary.Add "ten","diez"
EnglishNumber="four"
SpanishNumber=MyDictionary.Item (EnglishNumber)
Response.Write(SpanishNumber)
%>		 1
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How the script works
  • Fist we have define a Dictionary named "Mydictionary" (line 2)
  • We have add to the dictionary the data corresponding to the different number in English and Spanish (lines 4 to 13).
    • When adding pairs of English and Spanish numbers to the Dictionary object, the number writen in English is a Key, and the number writen in Spanish a Item.
  • In line 15 we have defined a variable named EnglishNumber and we have provided a value for this variable (in red).
  • In line 16 we have defined a new variable (SpanishNumber) and we have get its value from the dictionary by indicating we want to get the Item corresponding to a specific Key (EnglishNumber).
  • In line 17 the translated number is send to our visitor. The response will be "cuatro".
We may change the values in our dictionary by using this kind of code:
  • MyDictionary.Key ("one")="1" example
    • In our original script the key "one" will be substitute by a new key value ("1"). The item "uno" will not be changed.
  • MyDictionary.Item ("two")="2" example
    • In our original script the item corresponding to key "two" will be substitute by a new item value ("2"). The key "two" will not be changed.
We may display the number of element pairs in the dictyonary by using this code: If we want to check whether a key exists in our dictionary before responding to our visitor we will use this kind of comparisoncode
 
if MyDictionary.Exists ("ten")=True  then
           Response.Write("this key is included in the dictionary")
lse
           Response.Write("Error: no such a key in the dictionary")
end if
Example: Translation of a number from English to Spanish
This example uses most of the elements explained above.
  • If there is no information posted to the script (line 6), the script will send to the visitor the form in the  Sendform() subrouting (lines 34-40).
  • When a request to translate a number is get the script will check whether the number corresponds to a key in the dictionary (line 25). If the response is afirmative the corresponding item is send to the visitor. In case the key does not exists, a "No translation available" response is send to the visitor (line 29).
translation.asp
<html>
<title>Page under construction</title>
<body> <% 
if request.form="" then
      Sendform()
else
      SET MyDictionary=CreateObject("Scripting.Dictionary")
MyDictionary.Add "one","uno"
MyDictionary.Add "two","dos"
MyDictionary.Add "three","tres"
MyDictionary.Add "four","cuatro"
MyDictionary.Add "five","cinco"
MyDictionary.Add "six","seis"
MyDictionary.Add "seven","siete"
MyDictionary.Add "eight","ocho"
MyDictionary.Add "nine","nueve"
MyDictionary.Add "ten","diez"
      EnglishNumber=request.form("EnglishNumber")
      Response.Write("English number: " & EnglishNumber)       if MyDictionary.Exists (EnglishNumber)=True then
           SpanishNumber=MyDictionary.Item (EnglishNumber)
           Response.Write("<BR>Spanish number: " & SpanishNumber)
     else
           Response.Write("<BR>Spanish number: " & "No translation available")
     end if
end if
%>
<% Sub Sendform() %>
<form action=translation.asp method=post>
Write a number in English<BR>
<input type=text size=30 name=EnglishNumber><BR>
<input type=submit Value="Enter to my Secret Page">
</form>
<% End Sub %>
</body>
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  Example: Password protected information
In this example keys and items are used as usernames and passwords. It is very similar to the one above.
 
 
secretpage.asp
<% 
if request.form="" then
      Sendform()
else
      SET MyDictionary=CreateObject("Scripting.Dictionary")
      MyDictionary.Add "John","123"
      MyDictionary.Add "Peter","456"
      MyDictionary.Add "Anna","789"
      Username=request.form("Username")
      Password=request.form("password")       if MyDictionary.Exists (Username)=True AND Password=MyDictionary.Item (Username) then
            SecretInfo() 
     else
           Response.Write("Error: incorrect userame or password")
     end if
end if
%>
<% Sub Sendform() %>
<form action=secretpage.asp method=post>
Username: <input type=text size=30 name=Username><BR>
Password: <input type=password size=30 name=Password><BR>
<input type=submit Value="Submit">
</form>
<% End Sub %>
 
<% Sub SecretInfo() %>
<html>
<head>
<title>My Secret Page</title>
</head>
<body bgcolor=FFFFFF>
<center>
<h1>This is my secret info</h1>
Hello !<BR>
Do you want to be my friend?
</center>
</body>
</html>
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Cookies method is very similar to Session method: the basic difference is that with Cookies method the information is save in the clients computer and not in the server, so it is more suitable for sites with a lot of visitors. This method implies sending information to the client and requesting it whenever the information is needed. Additionally, we will learn how to delete the information save in the clients computer when it is not necessary anymore.
When the visitor gets to our asp file we may save information related with him in his computer. The order will be like this one:
<% response.Cookies ("whatever")="information" %>
When this line is executed, the visitor will have the information in his computer, and whenever we need that information, we may request it using this code:
<% =request.Cookies ("whatever") %>
or
<% variable1=request.Cookies ("whatever") %>
 
Let's try an example using Cookies method: let's consider we have visitors checking our site several times and we want to let them know how many times they have accessed to our computer.
 
cookiesexample.asp
<% If Request.Cookies ("NumberVisits")="" Then %>
        <% Response.Cookies ("NumberVisits")=1 %>
        This is your first visit to this page. Welcome.
<% Else %>
       <%  VarNumberVisits=Request.Cookies ("NumberVisits")
       VarNumberVisits=VarNumberVisits+1
       Response.Cookies("NumberVisits")=VarNumberVisits %>        Welcome back to this page. You have visited this page <% =VarNumberVisits %> times.
      <BR>Check my great links
      <BR>.....
      <BR>.....
<% End If %>
Cookies method may be used to show visitors specific information we have requested throw a form, as for example a list of links related to a specific theme, information to allow access to the content of a page or to personalize the page (background color, frames or not frames...), information to fill a form automatically, etc.

 FORMS WITH GET METHOD


<html>
<body>
<form action="demo_reqquery.asp" method="get">
Your name: <input type="text" name="fname" size="20" />
<input type="submit" value="Submit" />
</form>
<%
dim fname
fname=Request.QueryString("fname")
If fname<>"" Then
      Response.Write("Hello " & fname & "!<br />")
      Response.Write("How are you today?")
End If
%>
</body>
</html>

FORMS WITH POST METHOD

<html>
<body>
<form action="demo_simpleform.asp" method="post">
Your name: <input type="text" name="fname" size="20" />
<input type="submit" value="Submit" />
</form>
<%
dim fname
fname=Request.Form("fname")
If fname<>"" Then
      Response.Write("Hello " & fname & "!<br />")
      Response.Write("How are you today?")
End If
%>
</body>
</html>


CDOSYS is a built-in component in ASP. This component is used to send e-mails with ASP.

Sending e-mail with CDOSYS

CDO (Collaboration Data Objects) is a Microsoft technology that is designed to simplify the creation of messaging applications.
CDOSYS is a built-in component in ASP. We will show you how to use this component to send e-mail with ASP.

How about CDONTs?

Microsoft has discontinued the use of CDONTs on Windows 2000, Windows XP and Windows 2003. If you have used CDONTs in your ASP applications, you should update the code and use the new CDO technology.

Examples using CDOSYS

Sending a text e-mail:
<%
Set myMail=CreateObject("CDO.Message")
myMail.Subject="Sending email with CDO"
myMail.From="mymail@mydomain.com"
myMail.To="someone@somedomain.com"
myMail.TextBody="This is a message."
myMail.Send
set myMail=nothing
%>
Sending a text e-mail with Bcc and CC fields:
<%
Set myMail=CreateObject("CDO.Message")
myMail.Subject="Sending email with CDO"
myMail.From="mymail@mydomain.com"
myMail.To="someone@somedomain.com"
myMail.Bcc="someoneelse@somedomain.com"
myMail.Cc="someoneelse2@somedomain.com"
myMail.TextBody="This is a message."
myMail.Send
set myMail=nothing
%>
Sending an HTML e-mail:
<%
Set myMail=CreateObject("CDO.Message")
myMail.Subject="Sending email with CDO"
myMail.From="mymail@mydomain.com"
myMail.To="someone@somedomain.com"
myMail.HTMLBody = "<h1>This is a message.</h1>"
myMail.Send
set myMail=nothing
%>
Sending an HTML e-mail that sends a webpage from a website:
<%
Set myMail=CreateObject("CDO.Message")
myMail.Subject="Sending email with CDO"
myMail.From="mymail@mydomain.com"
myMail.To="someone@somedomain.com"
myMail.CreateMHTMLBody "http://www.w3schools.com/asp/"
myMail.Send
set myMail=nothing
%>
Sending an HTML e-mail that sends a webpage from a file on your computer:
<%
Set myMail=CreateObject("CDO.Message")
myMail.Subject="Sending email with CDO"
myMail.From="mymail@mydomain.com"
myMail.To="someone@somedomain.com"
myMail.CreateMHTMLBody "file://c:/mydocuments/test.htm"
myMail.Send
set myMail=nothing
%>
Sending a text e-mail with an Attachment:
<%
Set myMail=CreateObject("CDO.Message")
myMail.Subject="Sending email with CDO"
myMail.From="mymail@mydomain.com"
myMail.To="someone@somedomain.com"
myMail.TextBody="This is a message."
myMail.AddAttachment "c:\mydocuments\test.txt"
myMail.Send
set myMail=nothing
%>
Sending a text e-mail using a remote server:
<%
Set myMail=CreateObject("CDO.Message")
myMail.Subject="Sending email with CDO"
myMail.From="mymail@mydomain.com"
myMail.To="someone@somedomain.com"
myMail.TextBody="This is a message."
myMail.Configuration.Fields.Item _
("http://schemas.microsoft.com/cdo/configuration/sendusing")=2
'Name or IP of remote SMTP server
myMail.Configuration.Fields.Item _
("http://schemas.microsoft.com/cdo/configuration/smtpserver")="smtp.server.com"
'Server port
myMail.Configuration.Fields.Item _
("http://schemas.microsoft.com/cdo/configuration/smtpserverport")=25
myMail.Configuration.Fields.Update
myMail.Send
set myMail=nothing
%>
 

Open and Read content from a text file
Example 1: This one will be the basic code we need to open a text file:
 
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12		 <%
Set fs = CreateObject("Scripting.FileSystemObject") Set wfile = fs.OpenTextFile("c:\Mydir\myfile.txt")
filecontent = wfile.ReadAll
wfile.close
Set wfile=nothing
Set fs=nothing
response.write(filecontent)
%>
Line 2 will create the appropriate environment which allows to perform the operations involving files in the server. We have defined a variable named "fs" to do it  (we may change the name of this variable).
In line 4 we have create a new variable named "wfile" and we have apply the method OpenTextFile to variable "fs". We have also define which is the exact location of the file we want to open in this line (the complete path is necessary).
In line 5 we have read all the content of the file to a variable named "filecontent" using the instruction "ReadAll".
Lines 7 to 9 are use to let the server know we have finished all operations involving files.
In line 11 we have response to the client with the content in the variable "filecontent".
 
Example 2: Let's suppose we have a file with different kind of information in each line (a name in the first line, the last name in the second one, and the age in the third one), and we want to use them separately. This one will be the script we may use:
 
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17		 <%
Set fs = CreateObject("Scripting.FileSystemObject") Set wfile = fs.OpenTextFile("c:\Mydir\myfile.txt")
firstname = wfile.ReadLine
lastname = wfile.ReadLine
theage = wfile.ReadLine
wfile.close
Set wfile=nothing
Set fs=nothing
%>
Your first name is <% =firstname %><BR>
Your last name is <% =firstname %><BR>
Your are <% =firstname %> years old<BR>
This example is very similar to the previous one, but in this case each line we have read from "myfile.txt" has been saved to a different variable (lines 5 to 7), and they have been used in lines 15 to 17 to respond to the client.
Example 3: This example will read all lines in the file, and the response page will include the content of each line with its line number.
 
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Set fs = CreateObject("Scripting.FileSystemObject") Set wfile = fs.OpenTextFile("c:\Mydir\myfile.txt")
counter=0
do while not wfile.AtEndOfStream
 counter=counter+1
 singleline=wfile.readline
 response.write (counter & singleline & "<br>")
loop
wfile.close
Set wfile=nothing
Set fs=nothing
%>
In line 6 we will define the variable "counter", and in line 7 to 11 we will repeated instructions within the Do_While _Loop until the file does not reach the end of the file (the condition is  "not wfile.AtEndOfStream").
Example 4: Let's suppose we have a file with a number in line 1 and a second number in line 2.
 
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Set fs = CreateObject("Scripting.FileSystemObject") Set wfile = fs.OpenTextFile("c:\Mydir\myfile.txt")
number1 = Clng(wfile.ReadLine)
number2= Clng(wfile.ReadLine)
number1and2 = number1 + number2
response.write (number1and2)
wfile.close
Set wfile=nothing
Set fs=nothing
%>
In the previous examples we were able to save the value in a line to a variable, but that variable was a string class variable. In this example we have saved the content of line 1 and line 2 to variables "number1" and number2" by using the function "Clng".  This function has allow us to add both numbers in line 9 and send the result to the client (line 10).
 


Create and Write a text file
Example 1: The basic code we need to create a file is very similar to that one we have used to open a file:
 
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14		 <%
thetext="Write this text in the file" Set fs = CreateObject("Scripting.FileSystemObject")
Set wfile = fs.CreateTextFile("c:\Mydir\myfile.txt", True)
wfile.Write (thetext)
wfile.close
Set wfile=nothing
Set fs=nothing
response.write("Text created")
%>
The differences to instructions when opening a file are line 6 and line 7:
The method used in line 6 is "CreateTextFile"; it is necessary to indicate the complete path to the file we want to create; in line 6 we may use the instruction True (to allow over-writing an existing file) or False (if the file exits, it is not over-written).
Line 7 will write in the file the string in variable "thetext".
 
 
We may also use this instruction to add content to the file
wfile.WriteLine (thetext1)
wfile.WriteLine (thetext2)
...
In this case we will write the content in variable "thetext1" in line 1, content in "thetext2" in line 2 etc.
 
 
Example 2: Let suppose we want to record the IP address of all visitor to our page to a file named "mylog.txt".
 
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VisitorsIP=Request.ServerVariables ("REMOTE_ADDR") Set fs = CreateObject("Scripting.FileSystemObject")
Set wfile = fs.OpenTextFile("c:\Mydir\mylog.txt", 8,false,0)
wfile.WriteLine (VisitorsIP)
wfile.close
Set wfile=nothing
Set fs=nothing
response.write("IP registered")
%>
The IP address is requested in line 2 (check Functions and Procedures). In this case we have open the file "mylog.txt" in line 6 with the instruction "forappending". this instruction will allow us to open the file and add at the end of it the IP address of our last visitor.

Global.asa is a text file locate in your main directory (/global.asa). Bellow is shown the basic extructure of a global.asa file.
 
global.asa
<SCRIPT LANGUAGE="VBScript" RUNAT="Server"> Sub Application_OnStart
........
End Sub
Sub Application_OnEnd
........
End Sub
Sub Session_OnStart
........
End Sub
Sub Session_OnEnd
........
End Sub
</SCRIPT>
This file will be activated in this cases:
  • When the first visitor accesses our pages
  • When a new session starts.
In both cases, we may determine a series of events to be execute in the file above.
  1. Application_OnStart
    It is execute before the first session is started.
  2. Application_OnEnd
    It is execute when the application is finished.
  3. Session_OnStart
    It is execute when the server creates a new session (when a new client acccesses our server).
  4. Session_OnEnd
    It is execute when a session is abandon of after certain period of time without contact between the client and the server (normaly after 20 minutes or so from the last request from a specific client, the server will consider he is not going to come back, so it will delete all the information related to that session).

Lets try a very simple example:
Active Users Counter
Just copy the code in the table to a text file and save it in the main directory of your site ("/global.asa").
 
global.asa
<SCRIPT LANGUAGE="VBScript" RUNAT="Server"> Sub Application_OnStart
application("activevisitors")=0
End Sub
Sub Application_OnEnd
End Sub
Sub Session_OnStart
application.lock
application("activevisitors")=application("activevisitors")+1
application.unlock
End Sub
Sub Session_OnEnd
application.lock
application("activevisitors")=application("activevisitors")-1
application.unlock
End Sub
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The first time a visitor gets to our pages, global.asa will be executed, and consequently, application("activevisitors") in line 4 will get a value equal to "0". Immediately (as a new session has started), in line 12, application("activevisitors") will be increased by one. Each time a new visitor gets to our pages application("activevisitors") will be increased by one, and identically, each time a session is finished, this parameter will be reduce by one (line 18).
In case we want to show the number of visitors in our page, we must use this kind of code :
 
index.asp
There are  <% =application("activevisitors") %> active visitors.


In this tutorial we will create a regular HTML page with a small javascript code, and we will use this javascript code to include in the page new information from a ".asp" file.
First, let´s check this two pages:
 
 
javascript.html
<html>
<title>My page</title>
<body> <script language="javascript" src="javascript.asp"></script>
</body>
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javascript.asp
document.write ("hello") 1
In the first file (javascript.html) we have include a javascript code in red, and within the code the file name from which we will get information to complete our page (src: source). So that we are asking for information to complete our page (javascript.html) to a different page (javascript.asp). This time we have only include the file name, but we may use the complete url even from a different site (for example: http://www.adifferentsite.com/javascript.asp).
In the second file (javascript.asp) we have include the information necessary to write in the document the word "hello". This time we have use ".asp" extensión for the second page even though other extensions are possible.
The resulting page in our example will be like this one:
 
javascript.html (resulting page)
hello
So we already know we are able to include a text generated in one page within a different one. As the information we are including can be generate within a ".asp" file, we can add information dinamically by using Active Server Pages.
Let´s try two examples:
    A very rudimentary banner rotator system
    A simple text hit counter
In case you are using ".asp" files whithin a site and the origen of the information we want to include in the page is originated in the same site, using any of those  system is not very convenient: the number of conections to the server will increase, and there may be an important delay.  In case you want to include information obtained from an asp script in several pages but you do not want to copy the asp script  in all of them, you may use the Include instruction, so that the script is only in one page, and by changing it you will change the results in several pages.
A very rudimentary banner rotator system
Our page is "mypage.html" and we are requesting information to complete it from "http://www.myadrotator.com/adrotator.asp" which may be located in the same or in a different site. The information provided by the second file will determinate the ad to be display in our page.
 
mypage.html
<html>
<title>My page</title>
<body> <script language="javascript" src="http://www.myadrotator.com/adrotator.asp"></script>
</body>
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adrotator.asp
<% 
if session("ad")="" then 
     session("ad")=0
end if if session("ad")=5 then 
   session("ad")=1 
else 
    session("ad")=session("ad")+1 
end if 
%> 
<% Select Case session("ad") %>
<% case 1 %>
     document.write ("<A HREF=http://www.1site.com">)
     document.write ("<IMG SCR=1.gif>")
     document.write ("</A>")
 <% case 2 %>
     document.write ("<A HREF=http://www.2site.com">)
     document.write ("<IMG SCR=2.gif>")
     document.write ("</A>")
<% case 3 %>
     document.write ("<A HREF=http://www.3site.com">)
     document.write ("<IMG SCR=3.gif>")
     document.write ("</A>")
<% case 4 %>
     document.write ("<A HREF=http://www.4site.com">)
     document.write ("<IMG SCR=4.gif>")
     document.write ("</A>")
<% case 5 %>
     document.write ("<A HREF=http://www.4site.com">)
     document.write ("<IMG SCR=4.gif>")
     document.write ("</A>")
<% End select %>		 1
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  • Lines 2-3. Each time a new visitor gets to  "http://www.myadrotator.com/adrotator.asp" a new session will be open, and by using the session method, we will define session("ad") value to 0. In case the visitor is not new, the value for session("ad") will exits, and that value will be keep.
  • Lines 6-10.  The value for Session("ad") is increased by one unless that value is 5 (which is the maximum value allowed in this script)
  • Lines 13-34. By using Select_case  the page will return the information necessary to display the appropiate ad at "mypage.html". The first time a visitor accesses our page the ad display will be the first one, the second time ad number two and so on. After 5 visits, the process will start again. We may easily increase the number of ads just by adding more obtions within Select_case  and setting the maximum number from 5 to the new maximum in line 6.
NOTE: when writing the javascript code you must be very carefull: do not include brakets within the brakets in the javascript code
    p.e.:    Correct: document.write ("<A HREF=http://www.4site.com">)
                Incorrect: document.write ("<A HREF="http://www.4site.com"">)
                Correct: document.write ("<A HREF='http://www.4site.com'">)
    You may include in the response as many lines like the ones above or any other javascript code. A simple text hit counter
Our page is "mypage.html" and we are requesting information to complete it from "http://www.mycounter.com/hitcounter.asp" which may be located in the same or in a different site. The information provided by the second file will allow to get a text with the number of hits in our page.
 
 
mypage.html
<html>
<title>My page</title>
<body> <script language="javascript" src="http://www.mycounter.com/hitcounter.asp"></script>
</body>
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hitcounter.asp
<% 
Wfile="c:\mydir\cgi-bin\hitcounter.txt" Set fs = CreateObject("Scripting.FileSystemObject")
Set a = fs.OpenTextFile(Wfile)
hits = Clng(a.ReadLine)
hits = hits + 1
a.close
Set a = fs.CreateTextFile(Wfile,True)
a.WriteLine(hits)
a.Close
%>
document. write ("Number of hits since 2002/01/01: <% =hits %>")		 1
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  • Lines 2. We will need a text file with a number as its unique content. The path to that file will be openned in variable "Wfile". Creating this page within cgi-bin directory is a good way to prevent visitor from accesing our counter (they will get an error when trying to access a ".txt
     file within cgi-bin directory).
  • Lines 4-8.  We will open our file, read the content to a variable ("hits"), and in line 7 the variable will be increased by one.
  • Lines 10-12 . We will create a new file with the same name (overwriting the previous file) with the content in "hits".
  • Line 14.  The response page will be a javascript code containing the number of hits.
Introduction
Instead of having our information (variables or numbers) in variables like Mydata1, Mydata2, Mydata3 etc, by using arrays our information will be in an unique variable. Let´s check an example:
 
 
array.asp

<html>
<title>My Array</title>
<body> <%
DIM MyData(2,2)
MyData (0,0) = "1"
MyData (0,1) = "2"
MyData (0,2) = "3"
MyData (1,0) = "4"
MyData (1,1) = "5"
MyData (1,2) = "6"
MyData (2,0) = "7"
MyData (2,1) = "8"
MyData (2,2) = "9"
Response.write (MyData (1,2)) 
%>
</body>
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21		 Line 6: In this example we have defined by using "DIM" an array named Mydata and we have defined the size of the array. We may consider the table bellow as the source of information for our array. 
 MyData
0
1
2
0
1
2
3
1
4
5
6
2
7
8
9
Lines 7-15. After defining the array we have assigned values to the array. 
Line 17. In the response page we will send the value assigned to MyData(1,2) in the array. The first number will be the row and the second the column, so that in our case the response page will show the value "6"
 
Very often, we will defined an array from data obtained from a table with only one column. Let´s check an example:
 
array2.asp

<html>
<title>My Array</title>
<body> <%
DIM MyData(9)
MyData (0) = "0"
MyData (1) = "1"
MyData (2) = "2"
MyData (3) = "3"
MyData (4) = "4"
MyData (5) = "5"
MyData (6) = "6"
MyData (7) = "7"
MyData (8) = "8"
MyData (9) = "9"
Response.write (MyData (5)) 
%>
</body>
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21		 Original table for the array in the script
 MyData  
0
1
1
4
2
7
3
 3
4
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5
 5
6
 6
7
 7
8
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9
 9
In the response page we will send the value assigned to MyData(5) in the array. The response page will return 5. 
 
It is also possible to define an array with more dimensions as for example MyData(5,5,5,5).
Working with Arrays
In the examples above we have defined all the values within the script one by one, but this assignation may be done in a different way, as it is described in the example bellow:
 
 
array3a.asp Resulting page
<pre>
<%
MyArray=Array(Zero,one,two,three,four,five,six,seven,eight,nine)
%> Thearray(0): <% =Thearray(0) %>
Thearray(1): <% =Thearray(1) %>
Thearray(2): <% =Thearray(2) %>
Thearray(3): <% =Thearray(3) %>
Thearray(4): <% =Thearray(4) %>
Thearray(5): <% =Thearray(5) %>
Thearray(6): <% =Thearray(6) %>
Thearray(7): <% =Thearray(7) %>
Thearray(8): <% =Thearray(8) %>
Thearray(9): <% =Thearray(9) %>
</pre>		 Thearray(0): Zero
Thearray(1): pne
Thearray(2): two
Thearray(3): three
Thearray(4): four
Thearray(5): five
Thearray(6): six
Thearray(7): seven
Thearray(8): eight
Thearray(9): nine
 
In this example the array has been create from a string, and each component of the array has been separated by a comma. The Array method will do it for us easily.
We may also want to use a different string with a different delimiter to define the components in our array:
 
array3b.asp Resulting page
<pre>
<%
TheText="Zero=one=two=three=four=five=six=seven=eight=nine"
Thearray=split (TheText,"=") 
%> Thearray(0): <% =Thearray(0) %>
Thearray(1): <% =Thearray(1) %>
Thearray(2): <% =Thearray(2) %>
Thearray(3): <% =Thearray(3) %>
Thearray(4): <% =Thearray(4) %>
Thearray(5): <% =Thearray(5) %>
Thearray(6): <% =Thearray(6) %>
Thearray(7): <% =Thearray(7) %>
Thearray(8): <% =Thearray(8) %>
Thearray(9): <% =Thearray(9) %>
</pre>		 Thearray(0): Zero
Thearray(1): pne
Thearray(2): two
Thearray(3): three
Thearray(4): four
Thearray(5): five
Thearray(6): six
Thearray(7): seven
Thearray(8): eight
Thearray(9): nine
 
In this example we have defined the variable TheText, and whithin this variable we have include strings separated by "=".
In the next line, we have split the variable TheText into an array of strings (Thearray).
Split command have been used to brake TheText and "=" has been used as a delimiter to separate the substrings.
In the response page we have indicated the individual values of Thearray one by one.
 
It may happend to have a variable we want to split, but we do not know how many substrings we may get. In that case  we may use ubound command to discover how many elements are in our array, and them we may use that value to write them by using a For-next loop (see example below).
 
array4.asp Resulting page
<pre>
<%
TheText="a,f,w,d,u,t,e,u,f,v,o"
Thearray=split (TheText,"=") 
%> How many String do I have in TheArray?
<% =ubound(Thearray)+1 %>
<% 
For n=0 to ubound(Thearray) 
  Response.write (Thearray(n) & "<BR>")
next 
%>
</pre>		 How many Strings do I have in TheArray?
10 a
f
w
d
u
t
e
u
f
v
o

  Filtering values from a array
In the next example we will filter the information in our array, and we will display only part of it.
 
array5.asp
<pre>
<%
dim MyArray(9)
MyArray (0) = "Zero"
MyArray (1) = "One"
MyArray (2) = "Two"
MyArray (3) = "Three"
MyArray (4) = "Four"
MyArray (5) = "Five"
MyArray (6) = "Six"
MyArray (7) = "Seven"
MyArray (8) = "Eight"
MyArray (9) = "Nine"
%>
  Find strings containing "t" (case sensitive)
   <% =join(filter(MyArray,"t",True,0),",") %>
Find strings containing "t"
   <% =join(filter(MyArray,"t",True,1),",") %>
Find strings which do not contain "t" (case sensitive)
   <% =join(filter(MyArray,"t",False,0),",") %>
Find strings which do not contain "t" 
   <% =join(filter(MyArray,"t",False,1),",") %>
</pre>		 Find strings containing "t" (case sensitive)
   Eight
Find strings containing "t"
   Two,Three,Eight
Find strings which do not contain "t" (case sensitive)
   Zero,One,Two,Three,Four,Five,Six,Seven,Nine
Find strings which do not contain "t" 
   Zero,One,Four,Five,Six,Seven,Nine
The array and the assignation of values has been done as usually, and in the second part of the script we have used some lines similar to this one:
      <% =join(filter(MyArray,"t",True,0),",") %>
In this lines we have filter the values at MyArray and we have join them.
 
filter(MyArray,"t",True,0)
This part of the line have search for "t" in MyArray.
    True means we have selected the strings containing the search string (in this case "t").
    False will indicate we are selecting the strings which do not content the search string.
    0 means our search is case sensitive (a binary comparation)
    1 will mean it is not a case sensitive search (a textual comparation)
join(filter(MyArray,"t",True,0),",")
The complete line will join the filtered strings with the delimiter indicated (in this case ",")
Creating a table from data in a string In order to undertand this script we will consider we have a table like the one bellow, and that this table was the original source of information we used to create our table:
 
Peter student Chicago 123
John teacher London 234
Sue Manager Sidney 789
From the table we got this three lines by separeting the values by commas: Peter,student,Chicago,123
John,teacher,London,234
Sue,Manager,Sidney,789
And finaly we conected the three lines by separeting the values with "/":
Peter,student,Chicago,123/John,teacher,London,234/Sue,Manager,Sidney,789
The string obtained was saved to a variable named Mydata in the script bellow. The resulting page will show  a table like the original. This script is not limited by number of rows or columns (the maximun amount of then is calculate each time we run the script).
 
Createatable.asp
<%
Mydata="Peter,student,Chicago,123/John,teacher,London,234/Sue,Manager,Sidney,789"
Createtable()
%> <% 
Sub CreateTable()
MyRows=split (Mydata,"/") 
RowsNumber=ubound(MyRows)
Response.write ("<table border=1>")
For i=0 to RowsNumber
 DatainRow=split (MyRows(i),",") 
        NumberofDatainRow=ubound(DatainRow)
    Response.write ("<tr>")
        For n=0 to NumberofDatainRow
     Response.write("<td>" & DatainRow(n) & "</td>")
    Next
    Response.write ("</tr>")
Next
Response.write ("</table>")
End Sub
%>
This script may be used for several porpouses: we may generate Mydata by filtering values from an array as shown bellow:
<%
Dim Myclients(3)
Myclients(0)="Peter Smith,Chicago,Manager,123"
Myclients(1)="John Smith,New York,Accountant,124"
Myclients(2)="George Smith,Chicago,Administration,245"
Myclients(3)="Sam Smith,Dallas,Consultant,567" SearchFor="Chicago"
Mydata=join(filter(Myclients,SearchFor,True,1),"/")
Createtable()
%>
 
This code in combination with Createtable() Subroutine in the previus example will display only the clients from Chicago. The SearchFor variable may be obtained from a form.
 
  Simple keyword search
In this example, in our first visit a form asking for a keyword will be display. After submitting the keyword  Toredirect() Subroutine will be activated.
In this Subroutine we have create two arrays: Myinfo has a description of the URL located at MyURL. In case the keyword is included in the description of the site, the visitor will be redirected to the corresponding URL. Both arrays may be very very long.
 
 
search.asp
<% if request.form="" them %>
  <form method=post action=search.asp>
  <input type=text name=keyword>
  <input type=Submit value=Search>
  </form>
<% 
else
  Toredirect()
end if 
%> <%
Sub Toredirect()
dim Myinfo(4)
Myinfo (0) = "Asp tutorial for beginners"
Myinfo (1) = "Displaying Date Time and Text"
Myinfo (2) = "Using Variables and Forms"
Myinfo (3) = "If...Then and For...Next instructions"
Myinfo (4) = "Do...Loop and Select...Case instructions"
dim MyURL(4)
MyURL (0) = "http://www.asptutorial.info"
MyURL (1) = "http://www.asptutorial.info/Datetime.htm"
MyURL (2) = "http://www.asptutorial.info/Forms.htm"
MyURL (3) = "http://www.asptutorial.info/if_then-for_next.htm"
MyURL (4) = "http://www.asptutorial.info/Do_loop-Select_case.htm"
Numberofpairs=ubound(Myinfo)
For n=0 to Numberofpairs
 if inStr(Myinfo (n), request.form ("keyword"))>0 then
   Response.redirect(MyURL(n))
 end if
Next
Response.write ("The keyword has not been found")
End Sub


We are trying this tutorial to be simple, so in this page we will request imagenes from a ".asp" page, but the imagen will not  be newly generated. The images will be already saved in our server .
First, let´s check this two pages:
 
 
showpicture.html
<html>
<title>My picture</title>
<body> <img src=mypicture.asp>
</body>
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mypicture.asp
<% response.ContentType ="image/GIF" %>
<!--#include virtual="mypicture.gif" -->		 1
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  • In the first file (showpicture.html) we have include in the html code the source for our picture ("mypicture.asp", instead of "mypicture.gif").
  • In the response page, first we have indicated whith kind of ContentType we are sending to the client (this time "image/GIF", and then by using "include/virtual" the file is send (in this case all files are in the same directory)

Let´s try an examples:
 
A rudimentary banner rotator system
Our page is "mypage.html" and we are requesting a picture to a file named "mypicture.asp". This file will send to the client one of the pictures available (in this case up to 5), and two variables will be set up:
  • session ("ad"): will be used to save a number, which is needed to determinate which ad to show each time
  • session ("linkto"): will be used to save the link corresponding to the ad shown.
mypage.html
<html>
<title>My page</title>
<body> <a href=adrotatorlink.asp><img src=mypicture.asp NOSAVE></a>
</body>
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mypictureasp
<% 
if session("ad")="" then 
     session("ad")=0
end if if session("ad")=5 then 
   session("ad")=1 
else 
    session("ad")=session("ad")+1 
end if 
response.ContentType ="image/GIF" 
%> 
<% Select Case session("ad") %>
<% case 1 
     session("linkto")="http://linkto1.com" %>
     <!--#include virtual="picture1.gif" -->
 <% case 2 
     session("linkto")="http://linkto2.com" %>
     <!--#include virtual="picture2.gif" -->
<% case 3 
     session("linkto")="http://linkto3.com" %>
     <!--#include virtual="picture3.gif" -->
<% case 4 
     session("linkto")="http://linkto4.com" %>
     <!--#include virtual="picture4.gif" -->
<% case 5 
     session("linkto")="http://linkto5.com" %>
     <!--#include virtual="picture5.gif" -->
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adrotatorlink.asp
response.redirect(session("linkto")) 1
"mypage.html"
At  "mypage.html" we have include the regular HTML code to show a picture. We have used within the code the instruction "NOSAVE", so the picture will not be saved in the clients cache.

"mypicture.asp"
  • Lines 2-3. Each time a new visitor gets to  "http://www.myadrotator.com/adrotator.asp" a new session will be open, and by using the session method, we will define session("ad") value to 0. In case the visitor is not new, the value for session("ad") will exits, and that value will be keep.
  • Lines 6-10.  The value for Session("ad") is increased by one unless that value is 5 (which is the maximum value allowed in this script)
  • Line 12. The ContentType is defined
  • Lines 15-31. By using Select_case  and depending on the value saved in the instruction session("ad"), we will define session("linkto"), which will be the url to which we will redirect our visitor in case the picture send to the browser is clicked. 
"adrotatorlink.asp"
After clicking the corresponding picture, and as we have already save the corresponding URL at session('linkto"), we will redirect the visitor to the correct URL.
NOTE:  By using "NOSAVE" code in our page, the client will no save the picture in the cache of the computer. It may be a problem for us: let´s suppose we have include this the same code in several pages within our site. Each time we visit a new page, session ("linkto") will be defined again, but in case the visitor clicks the back bottom of the browser and the picture show is the same one it was shown in our previous visit, when clicking the visitor will be redirect to a non-correct URL.


Connect to MS Access database from ASP

Connecting to MS Access database from Classic ASP can be accomplished in several ways. You can connect using OLEDB DSN-less connection, you can connect using ODBC connection or you can use DSN. 
1. Connect to a Microsoft Access Database from ASP using a DSN 

Set oConnection = Server.CreateObject("ADODB.Connection")
oConnection.Open "DSN=;UID=;PWD="
oConnection.Close
The ASP connection example above is very simple and all you need to do is to create a DSN for your MS Access database. 
2. Connect to a Microsoft Access Database from ASP using DSN-less ODBC connection

Set oConnection = Server.CreateObject("ADODB.Connection")
oConnection.Open "DRIVER={Microsoft Access Driver (*.mdb)};DBQ=" &
Server.MapPath("") & ";UID=;PWD="
oConnection.Close
Set oConnection = Nothing
This ASP MS Access connection example doesn’t require DSN, but requires that you have Microsoft Access Driver installed on your computer/server. 
3. Connect to a Microsoft Access Database from ASP using DSN-less OLEDB  connection 

Set oConnection = Server.CreateObject("ADODB.Connection")
oConnection.Open "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=" & 
Server.MapPath("") & ";"
oConnection.Close
Set oConnection = Nothing
This MS Access ASP connection example requires only the OLEDB provider to work. 

link for all my students for refrence:
http://www.webwiz.co.uk/kb/asp-tutorials/connecting-to-an-access-database.htm
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