HttpRequest在整个HttpModule中的生命周期

Http Request开始
|
HttpModule
|
HttpModule.BeginRequest()
|
HttpModule.AuthenticateRequest()
|
HttpModule.AuthorizeRequest()
|
HttpModule.ResolveRequestCache()
|
建立HttpHandler控制点
|
接着处理（HttpHandler已经建立,此后Session可用)
|
HttpModule.AcquireRequestState()
|
HttpModule.PreRequestHandlerExecute()
|
进入HttpHandler处理HttpRequest
|
HttpHandler.ProcessRequest()
|
返回到HttpModule接着处理（HttpHandler生命周期结束，Session失效）
|
HttpModule.PostRequestHandlerExecute()
|
HttpModule.ReleaseRequestState()
|
HttpModule.UpdateRequestCache()
|
HttpModule.EndRequest()
|
HttpModule.PreSendRequestHeaders()
|
HttpModule.PreSendRequestContent()
|
将处理后的数据返回客户端
|
整个Http Request处理结束