ASP Fundamentals
ASP Fundamentals
Active Server Pages (ASP) is Microsoft's server-side scripting technology for building dynamic web pages. ASP code runs on the web server (IIS) and generates HTML sent to the browser.
ASP File Structure
ASP files use the .asp extension. Server-side code is enclosed in <% %> delimiters:
<%@ Language="VBScript" %>
<!DOCTYPE html>
<html>
<head><title>My First ASP Page</title></head>
<body>
<h1>Hello, World!</h1>
<p>The current date and time is: <%= Now() %></p>
<p>Your IP address is: <%= Request.ServerVariables("REMOTE_ADDR") %></p>
</body>
</html>
Built-in Objects
| Object | Purpose | Example |
|---|---|---|
| Request | Read data from the client (form data, query strings, cookies, headers) | Request.Form("username") |
| Response | Send data to the client (HTML, cookies, redirects) | Response.Write "Hello" |
| Server | Server utility methods (path mapping, COM object creation, encoding) | Server.CreateObject("ADODB.Connection") |
| Session | Per-user state that persists across requests (20 min default timeout) | Session("UserID") = 42 |
| Application | Application-wide state shared by all users | Application("VisitCount") |
Request Object Examples
<%
' Query string: page.asp?id=5&name=John
Dim strID, strName
strID = Request.QueryString("id")
strName = Request.QueryString("name")
' Form data (POST)
Dim strUsername, strPassword
strUsername = Request.Form("username")
strPassword = Request.Form("password")
' Cookies
Dim strTheme
strTheme = Request.Cookies("theme")
' Server variables
Dim strMethod, strUserAgent
strMethod = Request.ServerVariables("REQUEST_METHOD")
strUserAgent = Request.ServerVariables("HTTP_USER_AGENT")
%>
Response Object Examples
<%
' Write output
Response.Write "<p>Welcome, " & Server.HTMLEncode(strName) & "</p>"
' Set a cookie
Response.Cookies("theme") = "classic"
Response.Cookies("theme").Expires = DateAdd("d", 30, Now())
' Redirect
Response.Redirect "login.asp"
' Set content type
Response.ContentType = "application/json"
%>