c# - 如何确定是否可以使用 CancellationTokenSource 取消某个异步任务？

Question

我想知道是否可以使用 CancellationTokenSource 取消任务。如何确定是否可以取消某个异步任务？

public async Task PlayerAccountDetails()
{
    CancellationTokenSource cts = new CancellationTokenSource();

    try
    {
        await UpdatePlayerCountryData("Germany", "Berlin");
    }
    catch (Exception ex)
    {
        var excep = ex.Message;
    }
}

private static async Task UpdatePlayerCountryData(string country, string city)
{
    var resultprofile = await PlayFabClientAPI.UpdateUserDataAsync(new PlayFab.ClientModels.UpdateUserDataRequest()
    {
        Data = new Dictionary<string, string>() {
               {"Country", country},
               {"City", city}},
               Permission = PlayFab.ClientModels.UserDataPermission.Public
    });

    if (resultprofile.Error != null)
        Console.WriteLine(resultprofile.Error.GenerateErrorReport());
    else
    {
        Console.WriteLine("Successfully updated user data");
    }
}

标签： c#

Answer 1

这是一个实际的例子：

class Program
{
    static void Main(string[] args)
    {
        var cancellationTokenSource = new CancellationTokenSource();
        var task = Task.Run(async () => await WatchYourCarBurn(cancellationTokenSource.Token));

        Task.Run(async () => await Task.Delay(5000)).Wait();
        Console.WriteLine("Too much time elapsed, cancel task.");
        cancellationTokenSource.Cancel();

        while (!task.IsCompleted && !task.IsCanceled)
        {

        }
    }

    private static async Task WatchYourCarBurn(CancellationToken token)
    {
        Console.WriteLine("You notice some fog");

        await Task.Delay(2000);

        token.ThrowIfCancellationRequested();

        Console.WriteLine("You notice some fire");

        await Task.Delay(2000);

        token.ThrowIfCancellationRequested();

        Console.WriteLine("You notice your car");

        await Task.Delay(2000);

        token.ThrowIfCancellationRequested();

        Console.WriteLine("You notice your car is burning");

        await Task.Delay(2000);

        token.ThrowIfCancellationRequested();

        Console.WriteLine("You watch your car burning");

        await Task.Delay(2000);
    }
}