Dear Sir

I have tried this one, But Page loader is there but it's not dissapper.

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="Server">
</asp:Content> 
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-select/1.12.2/js/bootstrap-select.min.js"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-select/1.12.2/css/bootstrap-select.min.css" />
 
<style type="text/css">
  .loader {
            position: fixed;
            left: 0px;
            top: 0px;
            width: 100%;
            height: 100%;
            z-index: 9999;
            background: url('Images/loading-spinner.gif') 50% 50% no-repeat rgb(249,249,249);
        }
</style>
<script type="text/javascript">
     $(window).load(function () {
         $(".loader").fadeOut("slow");
     })
</script>
<div class="loader"></div>