如何创建通用Task.ContinueWith扩展方法

Question

所以目前我有一个Task.ContinueWith扩展方法，如下所示：

public static Task ContinueWith_UsingSyncContextWorkaround(this Task task, Action<Task> continuationAction, CancellationToken cancellationToken, TaskContinuationOptions continuationOptions, TaskScheduler scheduler, SynchronizationContext sc)
{
    Action<Task> actionWithWorkaround = t =>
    {
        SynchronizationContext.SetSynchronizationContext(sc);
        continuationAction(t);
    };

    return task.ContinueWith(actionWithWorkaround, cancellationToken, continuationOptions, scheduler);
}

并且此方法工作正常，但它无法让我访问Task的结果，因此我想创建一个通用扩展方法。

我尝试过：

public static Task<T> ContinueWith_UsingSyncContextWorkaround(this Task<T> task, Action<Task<T>> continuationAction, CancellationToken cancellationToken, TaskContinuationOptions continuationOptions, TaskScheduler scheduler, SynchronizationContext sc)
{
    Action<Task<T>> actionWithWorkaround = t =>
    {
        SynchronizationContext.SetSynchronizationContext(sc);
        continuationAction(t);
    };

    return task.ContinueWith(actionWithWorkaround, cancellationToken, continuationOptions, scheduler);
}

但是这不会编译，因为

找不到类型或名称空间名称T

如何创建通用的Task.ContinueWith扩展方法？

Answer 1

public static Task<T> ContinueWithUsingSyncContextWorkaround<T>(this Task<T> task,
                                               Func<Task<T>, T> continuationFunc, 
                                               CancellationToken cancellationToken,
                                               TaskContinuationOptions continuationOptions,
                                               TaskScheduler scheduler,
                                               SynchronizationContext sc)
{
    Func<Task<T>, T> funcWithWorkaround = t =>
    {
        SynchronizationContext.SetSynchronizationContext(sc);
        return continuationFunc(t);
    };

    return task.ContinueWith<T>(funcWithWorkaround, cancellationToken,
                                continuationOptions, scheduler);
}