jquery validate 用alert提示错误

 jQuery().ready(function() {
            var validator = jQuery(".form1").validate({
                rules: {
                    docTypeId: "required",
                    "uploadFiles[0].file":"required"
                },
                messages: {
                    docTypeId: "请选择****",
                     "uploadFiles[0].file":"请选择文件"
                },                 
                showErrors: function(errorMap, errorList) {
                    var msg = "";
                    jQuery.each(errorList, function(i, v) {
                        msg += (v.message + "\r\n");
                    });
                    if (msg != ""){
                        alert(msg);
                   } 
                }
            });
            jQuery("#btn_submit").click(function() {
                var check = validator.form();
                if (check) {
                    jQuery(".form1").submit();
                }
            });
        });