问AJAX提交-状态200出现错误

EN

$(document).ready(function () {
    $("#dialog-form").dialog({
        autoOpen: false,
    });

    $("#add-course").click(function () {
        $("#dialog-form").dialog("open");
        return false;
    });

    $("#btncancel").click(function () {
        $("#dialog-form").dialog("close");
    });

    $('#<%=btnsubmit.ClientID%>').on('click', function (e) {
        e.preventDefault();
        var courseDetails = {};
        courseDetails.Code = $('#<%=addcode.ClientID%>').val();
        courseDetails.Name = $('#<%=addname.ClientID%>').val(); 

        var jsonData = JSON.stringify({
            courseDetails: courseDetails
        });

        $.ajax({
            url: '<%=ResolveUrl("updatetest.aspx/addCourseSP") %>',
            type: "POST",
            data: jsonData,
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: OnSuccess,
            error: OnErrorCall,
        });

        function OnSuccess(response, jqXHR, textStatus, errorThrown) {
            var result = response.d;
            if (result == "success") {
                $("#msg").html("Success");
                $("#dialog-form").dialog("close");
            } else {
                $("#msg").html("jqXHR: " + JSON.stringify(jqXHR) + " " + "AJAX error: " + textStatus + ' : ' + errorThrown);
            }
        }

        function OnErrorCall() {
            $("#msg").html("error");
        }
    });
});