Guys I got the solution for this ..
<script type="text/javascript">
var prm = Sys.WebForms.PageRequestManager.getInstance();
prm.add_initializeRequest(prm_InitializeRequest);
prm.add_endRequest(prm_EndRequest);
// Called when async postback begins
function prm_InitializeRequest(sender, args) {
var panelProg = $get('divImage');
panelProg.style.display = '';
// Disable control that caused a postback
$get(args._postBackElement.id).disabled = true;
}
// Called when async postback ends
function prm_EndRequest(sender, args) {
var panelProg = $get('divImage');
panelProg.style.display = 'none';
$get(sender._postBackSettings.sourceElement.id).disabled = false;
}
</script>
<div id="divImage" class="loader" style="display: none">
<img alt="Loading... Please wait!" src="../Images/loader.gif" width="100" height="100" />
</div>
<style type="text/css">
.loader
{
position: fixed;
z-index: 100000000;
top:40%;
left:45%;
background-color:white;
}
</style>
Now it's working perfectly fine for me.
