httpapplication事件執行順序
instances of the <b>httpapplication</b> class are created in the asp.net infrastructure, not by the user directly. one instance of the <b>httpapplication</b> class is used to process many requests in its lifetime; however, it can process only one request at a time. thus, member variables can be used to store per-request data.
an application executes events that are handled by modules or user code that is defined in the global.asax file in the following sequence:
beginrequest
authenticaterequest
postauthenticaterequest
authorizerequest
postauthorizerequest
resolverequestcache
postresolverequestcache
after the <b>postresolverequestcache</b> event and before the postmaprequesthandler event, an event handler (a page corresponding to the request url) is created.
<b>postmaprequesthandler</b>
acquirerequeststate
postacquirerequeststate
prerequesthandlerexecute
the event handler is executed.
postrequesthandlerexecute
releaserequeststate
postreleaserequeststate
after the <b>postreleaserequeststate</b> event, response filters, if any, filter the output.
updaterequestcache
postupdaterequestcache
endrequest