How to Override the __doPostBack function ?
Well it sometime things are looks difficult when you work simple traditional way.Sometime back i was trying to submit server data from JavaScript confirm message box. I did by calling __doPostBack function in asp.net.Which looks something like this
btnSuresh.Attributes.Add("onclick", "if(!confirm('Are you sure you want to delete?')){return false;}__doPostBack();");
On other hand, It is also sometime good to overwrite override the __doPostBack function and write your own javascript code.
<script language="javascript">
var oldPostBack
function window.onload()
{
oldPostBack = __doPostBack;
__doPostBack = MyFuntion;
}
function MyFuntion()
{
//Write you own code
}
</script>
For More
http://www.dotnet247.com/247reference/msgs/15/77421.aspx
http://weblogs.asp.net/vga/archive/2004/03/01/NoMoreHijackingOfDoPostBackInWhidbey.aspx
Cheers..
Suresh Behera