Just the Facts

• A pipeline of run-time modules receive from IIS an incoming HTTP packet and make it evolve from a protocol-specific payload up to an instance of a class derived from Page.

• The page class required to serve a given request is dynamically compiled on demand when first required in the context of a Web application.

• The page class compiled to an assembly remains in use as long as no changes occur to the linked .aspx source file or the whole application is restarted.

• Each page class is an HTTP handler that is, a component that the run time uses to service requests of a certain type.

• The ASP.NET 2.0 code-behind model employs partial classes to generate missing declarations for protected members that represent server controls. This code was autogenerated by Visual Studio .NET 2003 and placed in regions.

• ASP.NET pages always post to themselves and use the view state to restore the state of controls existing when the page was last generated on the server.

• The view state creates the illusion of a stateful programming model in a stateless environment.

• Processing the page on the server entails handling a bunch of events that collectively form the page life cycle. A deep understanding of the page life cycle is key to diagnosing possible problems and implementing advanced features quickly and efficiently.