In ASP.NET which event fires when page is loaded in clients browers. Init, Load, PreRender event fires when page is not loaded in clients browser.
Basically I have to some work when page is displayed in client's browser..
Edit: The best answer I can come up with using only ASP.NET is OnLoadComplete()
There is no event like that. To understand why you have to understand how a web application works. The ASP.NET code runs on the server to build the contents of the web page, then the server sends the contents down to the browser which is running on the user's machine.
So the document being opened in the browser isn't even part of the ASP.NET page lifecycle. As far as ASP.NET is concerned, that page is now the browser's problem and it has already moved on to something else.
To make an analogy, it is like wanting to be notified when someone receives a letter that you (ASP.NET) mailed to them. Unless the recipient (the Browser) sends back some kind of communication there is no way for the sender (ASP.NET) to know what is happening somewhere else.