hi Sashibhusan Meher,
This is because you need to register the script once to DOM, Try doing the below things
write the window.open code in a javascript function
like
<script language="javascript">
function popUp()
{
window.open('detailsofjobseeker.aspx', '', '', 'height=200,width=400'); return false;
}
</script>
then in pageLoad()
write like this..
protected void Page_Load(object sender, EventArgs e)
{
String name1 = "PopupScript";
String text1 = "<script type=\"text/javascript\">popUp();";
RegisterStartupScript(name1, text1);
}
and while calling.. write like this
btn.Attributes.Add("onClick", "popUp();");
it may work.
Thanks.