/// <summary>
/// 获取待执行任务
/// </summary>
/// <typeparam name="TResult"></typeparam>
/// <param name="function"></param>
/// <returns></returns>
private AwaitableTask <TResult> GetExecutableTask <TResult>(Func <TResult> function)
{
var awaitableTask = new AwaitableTask <TResult>(new Task <TResult>(function), Guid.NewGuid().ToString());
SetLastTask(awaitableTask);
return(awaitableTask);
}
/// <summary>
/// 获取待执行任务
/// </summary>
/// <typeparam name="TResult"></typeparam>
/// <param name="function"></param>
/// <returns></returns>
private AwaitableTask <TResult> GetExecutableTask <TResult>(Func <TResult> function)
{
var awaitableTask = new AwaitableTask <TResult>(new Task <TResult>(function));
AddPenddingTaskToQueue(awaitableTask);
return(awaitableTask);
}
/// <summary>
/// 获取待执行任务
/// </summary>
/// <param name="action"></param>
/// <returns></returns>
private AwaitableTask GetExecutableTask(Action action)
{
var awaitableTask = new AwaitableTask(new Task(action), Guid.NewGuid().ToString());
SetLastTask(awaitableTask);
return(awaitableTask);
}
/// <summary>
/// 获取待执行任务
/// </summary>
/// <param name="action"></param>
/// <returns></returns>
private AwaitableTask GetExecutableTask(Action action)
{
var awaitableTask = new AwaitableTask(new Task(action));
AddPenddingTaskToQueue(awaitableTask);
return(awaitableTask);
}
/// <summary>
/// 设置最后一个task
/// </summary>
/// <param name="task"></param>
/// <returns></returns>
private void SetLastTask(AwaitableTask task)
{
//添加队列，加锁。
lock (_lockObject)
{
_lastTask = task;
}
}
/// <summary>
/// 添加待执行任务到队列
/// </summary>
/// <param name="task"></param>
/// <returns></returns>
private void AddPenddingTaskToQueue(AwaitableTask task)
{
//添加队列，加锁。
lock (_queue)
{
_queue.Enqueue(task);
//开始执行任务
_autoResetEvent.Set();
}
}
private bool TryGetNextTask(out AwaitableTask task)
{
task = null;
while (_queue.Count > 0)
{
//获取并从队列中移除任务
if (_queue.TryDequeue(out task) && (!AutoCancelPreviousTask || _queue.Count == 0))
{
//设置进行中的异步操作无效
_lastDoingTask?.MarkTaskInvalid();
_lastDoingTask = task;
return(true);
}
//并发操作，设置任务不可执行
task.SetNotExecutable();
}
return(false);
}
/// <summary> /// 任务等待器 /// </summary> /// <param name="awaitableTask"></param> public TaskAwaiter(AwaitableTask awaitableTask) => _awaitableTask = awaitableTask;