Programming Microsoft® ASP.NET 3.5

Chapter 18. HTTP Handlers and Modules

HTTP modules and HTTP handlers are fundamental pieces of the ASP.NET architecture. HTTP handlers and modules are truly the building blocks of the .NET Web platform. Any requests for an ASP.NET managed resource is always resolved by an HTTP handler and passes through a pipeline of HTTP modules. After the handler has processed the request, the request flows back through the pipeline of HTTP modules and is finally transformed into markup for the caller.

An HTTP handler is the component that actually takes care of serving the request. It is an instance of a class that implements the IHttpHandler interface. The ProcessRequest method of the interface is the central console that governs the processing of the request. ...