How to Store the time i DB on the Closing of Browser/Crash

Question

i want to Store the Browser Closing time in DataBase .So tell me which event is Fired on the Browser Closing/ Crash.

 

i have Coded in the Global.asax Page .. on Session_End Event but it's Worked only on the Button Click not on the Browser Closing .

 

So Tell me the Answer . if it's Possible in Asp.net

 

 

thanku...