browser close event

Question

hello every one,

which event will fired in when browser closes in asp.net this is very urgent requirement  i have tried many ways.

just like 'onunload' and 'onbeforeunload' in javascript this is not working properly .i have also  tried  application_end event 

in global.asax  it is not firing when applcation closes .

need very urgent requirement .

Please share your ideas

Thanks,

Kalluri rakesh

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