Question

我试图处理ReactiveUI（7.4.0.0）命令中抛出的异常，但是在Visual Studio的“输出”窗口中，所有东西似乎都被放在了内部并且永远不会出现。我的测试代码是这样的：

class Program
{
    static void Main(string[] args)
    {
        try
        {
            var ata = ReactiveCommand.CreateFromTask(async () => await AsyncTaskThrowException());
            ata.ThrownExceptions.Subscribe(ex => Console.WriteLine($"async with await:\t{ex.Message}"));
            ata.Execute();
            // Exception thrown: 'System.InvalidOperationException' in System.Reactive.Windows.Threading.dll
            // Exception thrown: 'System.Exception' in Test.exe
            // Exception thrown: 'System.Exception' in mscorlib.dll

            var atna = ReactiveCommand.CreateFromTask(() => AsyncTaskThrowException(),null, RxApp.MainThreadScheduler);
            atna.ThrownExceptions.Subscribe(ex => Console.WriteLine($"async without await:\t{ex.Message}"));
            atna.Execute();
            // Exception thrown: 'System.InvalidOperationException' in System.Reactive.Windows.Threading.dll
            // Exception thrown: 'System.Exception' in Test.exe

            var ta = ReactiveCommand.CreateFromTask(async () => await TaskThrowException());
            ta.ThrownExceptions.Subscribe(ex => Console.WriteLine($"async without await:\t{ex.Message}"));
            ta.Execute();
            // Exception thrown: 'System.InvalidOperationException' in System.Reactive.Windows.Threading.dll
            // Exception thrown: 'System.Exception' in Test.exe

            var tna = ReactiveCommand.CreateFromTask(() => TaskThrowException());
            tna.ThrownExceptions.Subscribe(ex => Console.WriteLine($"async without await:\t{ex.Message}"));
            tna.Execute();
            // Exception thrown: 'System.InvalidOperationException' in System.Reactive.Windows.Threading.dll
            // Exception thrown: 'System.Exception' in Test.exe
            // Exception thrown: 'System.InvalidOperationException' in System.Reactive.Windows.Threading.dll

            var sf = ReactiveCommand.Create(() => ThrowException());
            sf.ThrownExceptions.Subscribe(ex => Console.WriteLine($"sync:\t{ex.Message}"));
            sf.Execute();
            // Exception thrown: 'System.InvalidOperationException' in System.Reactive.Windows.Threading.dll
        }
        catch (Exception ex)
        {
            Debug.WriteLine($"{nameof(ex.Message)}: {ex.Message}");
            Debug.WriteLine($"{nameof(ex.StackTrace)}: {ex.StackTrace}");
        }

        Console.ReadLine();
    }

    static async Task<string> AsyncTaskThrowException()
    {
        await Task.Delay(100);
        throw new Exception("Exception in async Task");
    }

    static Task<string> TaskThrowException()
    {
        throw new Exception("Exception in non-async Task");
    }

    static string ThrowException()
    {
        throw new Exception("Exception in sync func");
    }
}

如果我评论除了Exception之外的所有内容（包含有意的一个），则每次通话都会引发.Execute()。唯一打印的东西是第三个：

ReactiveCommand.CreateFromTask(() => TaskThrowException());

但仍然会抛出一些东西。

您能否帮助我理解为什么其他Exceptions没有被ThrownExceptions用途，以及如何完全处理错误以便他们不会在“输出”窗口中登录？

谢谢！

ReactiveUI的ReactiveCommand异常处理

0 个答案: