2. Harish Ranganathan
Application Platform Evangelist
Microsoft India

3. AGENDA
• HTTP Runtime • HTTP Context
• IIS & ASP.NET Relation • Global.asax
• HTTP Modules • Page Framework
• HTTP Handlers • Best Practices

4. HTTP Runtime
• A low-level HTTP processing infrastructure
• Logical replacement for ISAPI filters/extensions
• Ability to add, replace, or remove core pieces of
the product
• Benefits: Built-in thread pool, asynchronous
support, access to ASP.NET intrinsic objects

5. HTTP Runtime

6. Http Runtime

7. IIS-ASP.NET Relation
w3wp.exe (IIS 6.0)
http.sys (Kernel Mode)

8. IIS-ASP.NET Relation
Document types are
mapped to ISAPI
extensions in the IIS
Manager

9. IIS – ASP.NET Relation

10. HTTP Pipeline
HTTP
IIS aspnet_isapi HttpModules HttpHandler
Request

11. HTTP Modules
• Called before and after the handler executes
• Ability to intercept, participate or modify each
individual request into an application
Ex: Changing URL in request/response to hide
server names behind firewall.
• The HTTP Application provides several events
that modules can synchronize with

12. HTTP Modules
• Global Application Events:
– Start
– End
• Per request events (in order):
– BeginRequest – PreRequestHandlerExecute
– AuthenticateRequest – PostRequestHandlerExecute
– AuthorizeRequest – ReleaseRequestState
– ResolveRequestCache – UpdateRequestCache
– AcquireRequestState – EndRequest
• Per request events (non-deterministic):
– PreSendRequestHeaders
– PreSendRequestContent
– Error

13. HTTP Modules
Built-In HTTP Modules:
• Authentication Modules
• Authorization Modules
• OutputCache Module
• SessionState Module
• Configuring HTTP Modules
– Use httpModules section handler
• View the Machine.Config

14. HTTP Handlers
• Handlers:
– Are the endpoint in the request process
– Only one handler is invoked per request
• Examples
– ASP.NET Page Handler:
• Implements the ASP.NET Page Framework
• Processes all requests for .aspx pages
– ASP.NET Service Handler:
• Implements Web Services
• Processes all requests for .asmx pages
• Configuring HTTP Handlers

15. HTTP Handlers & Modules

16. HTTP Context
• Encapsulates all information about an individual
HTTP request
• ASP.NET intrinsic objects are exposed as properties
of the HttpContext
• Modules and Handlers get a reference to an
HttpContext object representing the current
request
• Flows through the lifetime of a request

17. HTTP Context
• ASP.NET supports all ASP classic members
Property Managed Class
– Request HttpRequest
– Response HttpResponse
– Server HttpServerUtility
– Session HttpSessionState
– Application HttpApplicationState
• ASP.NET adds several new and useful members
– Request.Files
– Response.Cache
– Error/User/Trace

18. Global.asax
• Extends on the familiar functionality of the
Global.asa
• Global.asax must be located in the root of a Web
application
• Enables easy handling of Application level events
without a custom HttpModule

19. Global.asax
Updates:
• Are automatically detected
• Causes the Global.asax to be recompiled
• Restarts the HTTP Application
• ASP.NET completes all current requests before
shutting down old application
• Fires Application_End event
• Shuts down App Domain

20. HTTP Context & Global.asax

21. Page Framework
• Overview
• Page Object
• Page Lifecycle
• Page Events
• Control Tree
• Page Directives

22. Page Framework
Page Object:
• Inherits from Control, implements IHttpHandler
• All .aspx pages inherit from Page
• Exposes the ASP.NET intrinsics
• Wires up events (Page_Load, Page_Init…)

23. Page Framework
Init
Page Lifecycle: LoadViewState
Constructor PostBack Data Processing
Load
ProcessRequest
(hidden from user)
PostBack Change Notification
PostBack Event Handling
PreRender
SaveViewState
Render
Dispose

24. Page Framework

25. Best Practices
• Return Multiple Resultsets
• Paged Data Access
• Connection Pooling
• ASP.NET Cache API
• Per Request caching
• Background Processing

26. Best Practices
• Page Output Caching and Proxy Servers
• Session State & Viewstate
• Debug vs. Release
• Exception Handling

29. Related Content
Breakout Sessions (session codes and titles)
Interactive Theater Sessions (session codes and titles)
Hands-on Labs (session codes and titles)
Hands-on Labs (session codes and titles)

30. Track Resources
Resource 1
Resource 2
Resource 3
Resource 4

31. © 2009 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should
not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS,
IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.