jquery ajax 有时候前台能接到数据 有时候接不到

$.ajax({
                url: strurl,
                data: $('#frm1').serialize(),
                type: "post",
                dataType: "text",
                cache: false,
                timeout:5000,
                beforeSend: function () // 设置表单提交前方法
                {

                },
                success: function (data, textStatus) {


                 var info=new Array();
                 info=data.split(',');
                 for (var i = 0; i < info.length; i++) {
               
                 $('#GridView1').find("input").each(function () {

                 if(info[i]==  jQuery.trim($('#GridView1').find('tr').eq($(this).parents('tr').index()+1).children('td').eq(3).text()) )
                 {
                 $(this).attr("checked", true);
                 }
                 });
               
                 }

            
                },
                error: function (ex) {

                }
            });