[UWP]Validator will throw an exception when call its method.

Question

I test the same code on console platform, it is no problem.

But when I call the method on UWP, it throw an exception to me.

Here is link for the test project: http://1drv.ms/1IOvtMc

Does anybody can contact MS to fix this?

Answer 1

Can you please provide details of the problem?

What exactly are you doing? What is the expected behavior? What is the actual behavior?

Including a zip (not .7z) file with a minimal repro is helpful but not sufficient.

Answer 2

The zip link: http://1drv.ms/1FxIJpw

Here is the console code:

using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using ValidationTest.Shared;

namespace ValidationTest.Console
{
    internal class Program
    {
        private static void Main(string[] args)
        {
            Person person = new Person() { Name = "Damn_it" };

            ValidationContext context = new ValidationContext(person) { MemberName = "Name" };
            List<ValidationResult> results = new List<ValidationResult>();

            bool isValidate = Validator.TryValidateProperty(person.Name, context, results);

            System.Console.WriteLine(isValidate);
            System.Console.ReadKey();
        }
    }
}

It will output: False.

And I copy this code to my UWP project.

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using ValidationTest.Shared;
using Windows.UI.Popups;
using Windows.UI.Xaml.Controls;

// The Blank Page item template is documented at http://go.microsoft.com/fwlink/?LinkId=402352&clcid=0x409

namespace ValidationTest.Universal
{
    /// <summary>
    /// An empty page that can be used on its own or navigated to within a Frame.
    /// </summary>
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
        }

        private async void GoTest()
        {
            Person person = new Person() { Name = "Damn_it" };

            ValidationContext context = new ValidationContext(person) { MemberName = "Name" };
            List<ValidationResult> results = new List<ValidationResult>();

            bool isValidate = Validator.TryValidateProperty(person.Name, context, results);

            await new MessageDialog(isValidate.ToString()).ShowAsync();
        }
    }
}

And run.

It throw an ArgumentNullException to me. If no problem, it should continue to run and show a message dialog which message is False.

You can see the three arguments of this method are both not null. So I think it is this API problem.

The person class definition:

using System.ComponentModel;
using System.ComponentModel.DataAnnotations;

namespace ValidationTest.Shared
{
    public class Person : INotifyPropertyChanged
    {
        public string _name;

        public event PropertyChangedEventHandler PropertyChanged;

        [StringLength(5)]
        public string Name
        {
            get
            {
                return _name;
            }
            set
            {
                _name = value; if (PropertyChanged != null)
                {
                    PropertyChanged(this, new PropertyChangedEventArgs(nameof(Name)));
                }
            }
        }
    }
}

And sorry for my terrible English.

Answer 3

Thanks for the clarification. I can reproduce this on Windows 10. The same code in a Windows 8.1 app works fine.

I'll file a bug on this.