您可以使用 TaskExtensions.Unwrap（）（这是 Task< Task> 的扩展方法）来展开外部任务并检索内部任务：

You can use TaskExtensions.Unwrap() (which is an extension method on Task<Task>) to unwrap the outter task and retrieve the inner one:

private async void Button2_Click(object sender, RoutedEventArgs e)
{
    var task = Task.FromResult(false);
    Task aggregatedTask = task.ContinueWith(task1 => InnerTask(task1.Result)).Unwrap();
    Console.WriteLine("1");
    await aggregatedTask;
    Console.WriteLine("4");
}

请注意，为了简化整件事，而不是 ContinueWith 样式延续，您可以等待完成任务：

Note that to simplify this entire thing, instead of ContinueWith style continuation you can await on your tasks:

private async void Button2_Click(object sender, RoutedEventArgs e)
{
    var task = Task.FromResult(false);

    Console.WriteLine("1");

    var result = await task;
    await InnerTask(result);

    Console.WriteLine("4");
}