ASP scripts are enclosed by <% and %>. To write some output to
<% response.write("I am Vyom!") %>
ASP uses VBScript as the default language. To use another scripting language,
insert a language specification at the top of the ASP page:
A D V E R T I S E M E N T
Forms and User Input
To collect values in a form with method="get",Request.QueryString is used.
Information sent from a form with the GET method has
limits on the amount of information to send and is visible to everyone (it will be displayed in the browser's address bar) and
To collect values in a form with method="post",Request.Form is used . Information sent from a form with the POST method has no limits on the amount of information to send and
is invisible to others.
To identify a user,a cookie is often used. A cookie is a small t
ext file that is stored on clientmachine that is embeded by the server
. Each time the same computer requests a page with a browser,
it will send the cookie too..
To create cookies,the Response.Cookies command is used :
With the #include directive,you can insert the content of one ASP file into another ASP file before the
server executes it. To create functions, headers, footers, or elements that will be reused on
multiple pages,the #include directive is used
<!--#include file ="somefile.inc"-->
To indicate a path beginning with a virtual
directory,use the virtual keyword. The following line would insert the contents of "header.inc"if a file named "header.inc" resides in a virtual directory
<!-- #include virtual ="/html/header.inc" -->
To indicate a relative path,use the file keyword . A relative path begins with
the directory that contains the including file. The
following line would insert "header.inc" in your file if you have a file in the html
directory, and the file "header.inc" resides in html\headers:
<!-- #include file ="headers\header.inc" -->
To include a file from a higher-level directory,use the file keyword with the syntax (..\) .
In an ASP application,the Global.asa file is an optional file that can contain declarations of
objects, variables, and methods that can be accessed by every page.
Note:Each application can only have one Global.asa file and the Global.asa file must be stored in the root directory of the
The Global.asa file can contain only the following:
the #include directive
Application and Session Events
when the application/session starts or application/session ends ,it is necessary to
tell the application and session objects in Glogal.asa about the work to be done.
The code for this is placed in event handlers. Note: To insert scripts in the Global.asa file, we have to put the
subroutines inside the HTML <script> tag,we do not use
<% and %>:
<script language="vbscript" runat="server">
' some code
' some code
' some code
' some code
By using the <object> tag,it is also possible to create objects with session or application scope in
Global.asa. Note: The <object> tag
should be outside the <script> tag!
The contents of a DLL file corresponding to a COM object is stored in a TypeLibrary.
The constants of the COM object can be accessed by including a call to the TypeLibrary in the Global.asa file,
and errors can be better reported by the ASP code.
You can declare the type libraries in Global.asa if your Web application relies on COM objects that have
declared data types in type libraries.
To store information about, or change settings for a user session,the Session object is used.
In a particular application,variables stored in the Session object hold information about one single user,
and are available to all pages .
Contents - Holds every item added to the session with script commands
StaticObjects - Holds every object added to the session with the
<object> tag, and a given session
Contents.Remove(item/index) - Deletes an item from the Contents
Contents.RemoveAll() - Deletes every item from the Contents collection
CodePage - Sets the code page that will be used to display dynamic content
LCID - Sets the locale identifier that will be used to display dynamic
SessionID - Returns the session id
Timeout - Sets the timeout for the session
Abandon - Kills every object in a session object
An application may be a group of ASP
files on the Web. To achieve some ourpose group of ASP file work together. In ASP ,The Application object is used to tie
these files together.To store and access variables from any page, just like
the Session object,the Application object is used. The difference is while with Sessions there
is one Session object for EACH user but there is one Application object for ALL users that can be shared.
In a particular application (like
database connection information),the Application object should hold information that
will be used by many pages .
Contents - Holds every item added to the application with script commands
StaticObjects - Holds every object added to the application with the
Contents.Remove - Deletes an item from a collection
Contents.RemoveAll - Deletes every item from a collection
Lock - Prevents a user from changing the application object properties
Unlock - Allows a user to change the application object properties
The Response Object
The Response Object is used to send output to the user from the server.
Cookies(name) - Sets a cookie value. If the cookie does not exist, it will
be created, and take the value that is specified
Buffer - Whether to buffer the output or not. When the output is buffered,
the server will hold back the response until all of the server scripts have
been processed, or until the script calls the Flush or End method. If this
property is set, it should be before the <html> tag in the ASP file
CacheControl - Sets whether proxy servers can cache the output or not.
When set to Public, the output can be cached by a proxy server
Charset(charset_name) - Sets the name of the character set (like
"ISO8859-1") to the content type header
ContentType - Sets the HTTP content type (like "text/html",
"image/gif", "image/jpeg", "text/plain").
Default is "text/html"
Expires - Sets how long a page will be cached on a browser before it
ExpiresAbsolute - Sets a date and time when a page cached on a browser
IsClientConnected - Checks if the client is still connected to the server
Pics(pics_label) - Adds a value to the pics label response header
Status - Specifies the value of the status line
AddHeader(name, value) - Adds an HTML header with a specified value
AppendToLog string - Adds a string to the end of the server log
BinaryWrite(data_to_write) - Writes the given information without
any character-set conversion
Clear - Clears the buffered output. Use this method to handle errors. If
Response.Buffer is not set to true, this method will cause a run-time error
End - Stops processing the script, and return the current result
Flush - Sends buffered output immediately. If Response.Buffer is not set
to true, this method will cause a run-time error
Redirect(url) - Redirects the user to another url
Write(data_to_write) - Writes a text to the user
When a browser asks for a page from a server, it is called a request. The
Request Object is used to get information from the user.
ClientCertificate - Holds field values stored in the client certificate
Cookies(name) - Holds cookie values
Form(element_name) - Holds form (input) values. The form must use
the post method
QueryString(variable_name) - Holds variable values in the query
ServerVariables(server_variable) - Holds server variable values
TotalBytes - Holds the total number of bytes the client is sending in the
body of the request
BinaryRead - Fetches the data that is sent to the server from the client
as part of a post request
The Server Object is used to access properties and methods on the server.
ScriptTimeout - Sets how long a script can run before it is terminated
CreateObject(type_of_object) - Creates an instance of an object
Execute(path) - Executes an ASP file from inside another ASP file.
After executing the called ASP file, the control is returned to the original
GetLastError() - Returns an ASPError object that will describe the error
HTMLEncode(string) - Applies HTML encoding to a string
MapPath(path) - Maps a relative or virtual path to a physical path
Transfer(path) - Sends all of the state information to another ASP
file for processing. After the transfer, procedural control is not returned
to the original ASP file
URLEncode(string) - Applies URL encoding rules to a string