How can I check event clicking the 'X' button

[Somyos]

How can I check event clicking the 'X' button in the upper right hand corner
of a window.
and call function or sub before close web page.

I'm using Asp.net on VS.NET

Thank.

 

[avnrao]

this requires client side scripting

write a javascript function and call it on onbeforeunload event of body tag.

Av.