Ajax功能不起作用

Ajax函数不更新数据。引导对话框中的数据加载，我需要通过更改来更新数据。我还要在浏览器中检查该值是否来自对话框，而不是发布到数据库中。

客户端：

$("#UpdateTbl").click(function () {
    var id = $(this).attr("edit-id");
    var user = {};
    debugger;
    user.DayDesc = $("#DaybookDesc1").val();
    user.VoucherNo = $("#Prifix1").val();
    user.VoucherNo1 = $("#Surffix1").val();


    $.ajax({
        type: "Post",
        contentType: "application/json; charset=utf-8",
        url: "DaybookMast.aspx/UpdateData",
        data:JSON.stringify( '{objEmployee: ' + JSON.stringify(user) + ', eid : ' + id + '}'),
        dataType: "json",
        success: function (data) {
            if (confirm("Are you want to change !") == true) {
                alert("Updated successfully");
            } else {
                alert("canceled changes");
            }

        },
        error: function (data) {
            alert("Error while Updating data of :" + id);
        }
    });
});

服务器端：

[WebMethod]
public static void UpdateData(DayBooks objEmployee, string eid) //Update data in database      
{
    using (var con = new SqlConnection(strConnection))
    {
        var query = "update DayBooks set DayDesc='" + objEmployee.DayDesc + "',VoucherNo='" + objEmployee.VoucherNo +
                    "',VoucherNo1='" + objEmployee.VoucherNo1 + "'where DayCode='" + eid + "'";
        con.Open();
        var cmd = new SqlCommand(query, con);
        cmd.ExecuteNonQuery();
        con.Close();
    }
}