public static string GetProductDetails()
    {
        // HttpContext is used here to access non static variable Session inside static method.
        DataTable dtProductDetails = new DataTable();
        decimal   client_alias     = Convert.ToDecimal(HttpContext.Current.Session["UserID"].ToString().Trim().Substring(0, 4));

        dtProductDetails = VPCRMSBAL.GetProductAssignment();
        String json = DataTableToJSONWithJavaScriptSerializer(dtProductDetails);

        return(json);
    }