Best Industrial Training in C,C++,PHP,Dot Net,Java in Jalandhar

Thursday, 27 February 2014

Display the Field Names and Field Values in ASP

<!DOCTYPE html>
<html>
<body>

<%
set conn=Server.CreateObject("ADODB.Connection")
conn.Provider="Microsoft.Jet.OLEDB.4.0"
conn.Open(Server.Mappath("/db/northwind.mdb"))
set rs = Server.CreateObject("ADODB.recordset")
rs.Open "Select * from Customers", conn

do until rs.EOF
    for each x in rs.Fields
       Response.Write(x.name)
       Response.Write(" = ")
       Response.Write(x.value & "<br>")
    next
    Response.Write("<br>")
    rs.MoveNext
loop

rs.close
conn.close
%>

</body>
</html>

Display the Field Names and Field Values in an HTML Table

We can also display the data from the "Customers" table inside an HTML table with the following lines (remember to save the file with an .asp extension):
<!DOCTYPE html>
<html>
<body>

<%
set conn=Server.CreateObject("ADODB.Connection")
conn.Provider="Microsoft.Jet.OLEDB.4.0"
conn.Open(Server.Mappath("/db/northwind.mdb"))

set rs = Server.CreateObject("ADODB.recordset")
rs.Open "SELECT Companyname, Contactname FROM Customers", conn
%>

<table border="1" width="100%">
<%do until rs.EOF%>
    <tr>
    <%for each x in rs.Fields%>
       <td><%Response.Write(x.value)%></td>
    <%next
    rs.MoveNext%>
    </tr>
<%loop
rs.close
conn.close
%>
</table>

</body>
</html>


Add Headers to the HTML Table

We want to add headers to the HTML table to make it more readable (remember to save the file with an .asp extension):
<!DOCTYPE html>
<html>
<body>

<%
set conn=Server.CreateObject("ADODB.Connection")
conn.Provider="Microsoft.Jet.OLEDB.4.0"
conn.Open(Server.Mappath("/db/northwind.mdb"))
set rs = Server.CreateObject("ADODB.recordset")
sql="SELECT Companyname, Contactname FROM Customers"
rs.Open sql, conn
%>

<table border="1" width="100%">
<tr>
<%for each x in rs.Fields
    response.write("<th>" & x.name & "</th>")
next%>
</tr>
<%do until rs.EOF%>
    <tr>
    <%for each x in rs.Fields%>
       <td><%Response.Write(x.value)%></td>
    <%next
    rs.MoveNext%>
    </tr>
<%loop
rs.close
conn.close
%>
</table>

</body>
</html>
Posted by at No comments:

Tuesday, 25 February 2014

Add a Record to a Table in a Database

Add a Record to a Table in a Database
We want to add a new record to the Customers table in the Northwind database. We first create a form that contains the fields we want to collect data from:
<html>
<body>

<form method="post" action="demo_add.asp">
<table>
<tr>
<td>CustomerID:</td>
<td><input name="custid"></td>
</tr><tr>
<td>Company Name:</td>
<td><input name="compname"></td>
</tr><tr>
<td>Contact Name:</td>
<td><input name="contname"></td>
</tr><tr>
<td>Address:</td>
<td><input name="address"></td>
</tr><tr>
<td>City:</td>
<td><input name="city"></td>
</tr><tr>
<td>Postal Code:</td>
<td><input name="postcode"></td>
</tr><tr>
<td>Country:</td>
<td><input name="country"></td>
</tr>
</table>
<br><br>
<input type="submit" value="Add New">
<input type="reset" value="Cancel">
</form>

</body>
</html>
When the user presses the submit button the form is sent to a file called "demo_add.asp". The "demo_add.asp" file contains the code that will add a new record to the Customers table:
<html>
<body>

<%
set conn=Server.CreateObject("ADODB.Connection")
conn.Provider="Microsoft.Jet.OLEDB.4.0"
conn.Open "c:/webdata/northwind.mdb"

sql="INSERT INTO customers (customerID,companyname,"
sql=sql & "contactname,address,city,postalcode,country)"
sql=sql & " VALUES "
sql=sql & "('" & Request.Form("custid") & "',"
sql=sql & "'" & Request.Form("compname") & "',"
sql=sql & "'" & Request.Form("contname") & "',"
sql=sql & "'" & Request.Form("address") & "',"
sql=sql & "'" & Request.Form("city") & "',"
sql=sql & "'" & Request.Form("postcode") & "',"
sql=sql & "'" & Request.Form("country") & "')"

on error resume next
conn.Execute sql,recaffected
if err<>0 then
  Response.Write("No update permissions!")
else
  Response.Write("<h3>" & recaffected & " record added</h3>")
end if
conn.close
%>

</body>
</html>


Posted by at No comments:

Tuesday, 11 February 2014

The Session object in ASP

The Session object

When you are working with an application on your computer, you open it, do some changes and then you close it. This is much like a Session. The computer knows who you are. It knows when you open the application and when you close it. However, on the internet there is one problem: the web server does not know who you are and what you do, because the HTTP address doesn't maintain state.
ASP solves this problem by creating a unique cookie for each user. The cookie is sent to the user's computer and it contains information that identifies the user. This interface is called the Session object.
The Session object stores information about, or change settings for a user session.
Variables stored in a Session object hold information about one single user, and are available to all pages in one application. Common information stored in session variables are name, id, and preferences. The server creates a new Session object for each new user, and destroys the Session object when the session expires.

When does a Session Start?

A session starts when:
  • A new user requests an ASP file, and the Global.asa file includes a Session_OnStart procedure
  • A value is stored in a Session variable
  • A user requests an ASP file, and the Global.asa file uses the <object> tag to instantiate an object with session scope

When does a Session End?

A session ends if a user has not requested or refreshed a page in the application for a specified period. By default, this is 20 minutes.
If you want to set a timeout interval that is shorter or longer than the default, use the Timeout property.
The example below sets a timeout interval of 5 minutes:
<%
Session.Timeout=5
%>
Use the Abandon method to end a session immediately:
<%
Session.Abandon
%>


Store and Retrieve Session Variables

The most important thing about the Session object is that you can store variables in it.
The example below will set the Session variable username to "Donald Duck" and the Session variable age to "50":
<%
Session("username")="Donald Duck"
Session("age")=50
%>
When the value is stored in a session variable it can be reached from ANY page in the ASP application:
Welcome <%Response.Write(Session("username"))%>
The line above returns: "Welcome Donald Duck".
You can also store user preferences in the Session object, and then access that preference to choose what page to return to the user.
The example below specifies a text-only version of the page if the user has a low screen resolution:
<%If Session("screenres")="low" Then%>
  This is the text version of the page
<%Else%>
  This is the multimedia version of the page
<%End If%>

Remove Session Variables

The Contents collection contains all session variables.
It is possible to remove a session variable with the Remove method.
The example below removes the session variable "sale" if the value of the session variable "age" is lower than 18:
<%
If Session.Contents("age")<18 then
  Session.Contents.Remove("sale")
End If
%>
To remove all variables in a session, use the RemoveAll method:
<%
Session.Contents.RemoveAll()
%>

Loop Through the Contents Collection

The Contents collection contains all session variables. You can loop through the Contents collection, to see what's stored in it:
<%
Session("username")="Donald Duck"
Session("age")=50

dim i
For Each i in Session.Contents
  Response.Write(i & "<br>")
Next
%>
Result:
username
age
If you do not know the number of items in the Contents collection, you can use the Count property:
<%
dim i
dim j
j=Session.Contents.Count
Response.Write("Session variables: " & j)
For i=1 to j
  Response.Write(Session.Contents(i) & "<br>")
Next
%>
Result:
Session variables: 2
Donald Duck
50

Loop Through the StaticObjects Collection

You can loop through the StaticObjects collection, to see the values of all objects stored in the Session object:
<%
dim i
For Each i in Session.StaticObjects
  Response.Write(i & "<br>")
Next
%>
Posted by at No comments:
Subscribe to: Posts (Atom)