Refresh Parent Window On Closing Of Child Window

<script language="javascript" type="text/javascript">
 function closeAddcostpopup(warrantid) {
   
        if (window.opener && !window.opener.closed)
        {
         
            if (warrantid != "") {
                window.opener.location.href = "EditViewReport.aspx?WarrantID=" + warrantid;
                window.close();
            }
   
        }
}
        </script>

on page load use below code:

 this.btnclose.Attributes.Add("OnClick", "javascript:return  closeAddcostpopup(" + hidden1 + ")");