Session_End只有在session server mode=Inproc时,才会触发。Once Abandon is called, the current session is no longer valid and a new session can be started. Abandon causes the End event to be raised (a new Start event is raised on the next request). The End event is supported only when Mode is InProc.
<sessionState
mode="InProc"
stateConnectionString="tcpip=127.0.0.1:42424"
sqlConnectionString="data source=127.0.0.1;Trusted_Connection=yes"
cookieless="false"
timeout="20"
/>