DispatcherUnhandledException在WPF中有什么用？UI异常处理

public partial class App : Application
{
    public App()
    {
        this.DispatcherUnhandledException += App_DispatcherUnhandledException;
    }

    void App_DispatcherUnhandledException(object sender, DispatcherUnhandledExceptionEventArgs e)
    {
        // 处理未处理的异常
        MessageBox.Show("发生未处理的异常：" + e.Exception.Message);

        // 可以记录异常信息到日志文件
        // LogException(e.Exception);

        // 设置 Handled 属性为 true，阻止应用程序崩溃
        e.Handled = true;
    }
}

await

Task.Result

TaskScheduler.UnobservedTaskException += (sender, e) =>
{
    Console.WriteLine("Task Exception: " + e.Exception.Message);
    e.SetObserved(); // 标记异常已被观察到，防止进程崩溃
};

Task.Run(() => { throw new Exception("Task Exception"); });

// 阻止程序立即退出，给 Task 一些时间执行
Thread.Sleep(1000);
GC.Collect(); // 强制垃圾回收，触发 UnobservedTaskException
GC.WaitForPendingFinalizers();

ICommand

CanExecute

public class MyViewModel : INotifyPropertyChanged
{
    private string _errorMessage;
    public string ErrorMessage
    {
        get { return _errorMessage; }
        set { _errorMessage = value; OnPropertyChanged(nameof(ErrorMessage)); }
    }

    public ICommand MyCommand { get; private set; }

    public MyViewModel()
    {
        MyCommand = new RelayCommand(ExecuteMyCommand, CanExecuteMyCommand);
    }

    private bool CanExecuteMyCommand(object parameter)
    {
        // 检查是否可以执行命令，防止异常
        return true; // 示例：总是可以执行
    }

    private void ExecuteMyCommand(object parameter)
    {
        try
        {
            // 执行操作，可能抛出异常
            DoSomething();
        }
        catch (Exception ex)
        {
            ErrorMessage = "发生错误：" + ex.Message;
            // 记录异常
        }
    }

    private void DoSomething()
    {
        // 模拟可能抛出异常的操作
        throw new Exception("模拟异常");
    }

    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged(string propertyName)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}