$(document).ready(function(){
    $("#btnSearch").click(function(){
        if($("#producttitle").val()==""){
            alert("请输入产品关键字！");
            $("#producttitle").focus();
            return;
       }
       var par_title=encodeURIComponent($("#producttitle").val());
       window.location.href="/ProductList.aspx?title="+par_title;
   });
});