C# Task 暂停与取消

前言：

①取消task任务之CancellationTokenSource的用法；

②task的线程管控方法Task..Wait(time)，Task.WaitAll()， Task.WaitAny(),task.ContinueWith.

1. 声明参数

CancellationTokenSource tokenSource = new CancellationTokenSource();
CancellationToken token = tokenSource.Token;
ManualResetEvent resetEvent = new ManualResetEvent(true);
2. 定义Task

Task task = new Task(async () => {
while (true) {
if (token.IsCancellationRequested) {
return;
}

// 初始化为true时执行WaitOne不阻塞
resetEvent.WaitOne();

// Doing something…….

// 模拟等待100ms
await Task.Delay(100);
}

}, token);

task.Start();
3. 暂停Task

resetEvent.Reset();
4. 继续Task

resetEvent.Set();
5. 取消Task

tokenSource.Cancel();
实例：

#region TASK用法举例
static void TasKTest()
{
//带返回值的task
Task<String> mytask = Task.Run(async () =>
{
await Task.Delay(5000);
return \”老铁666\”;
}, cancellationToken.Token);
//cancellationToken.Cancel();
while (!mytask.Wait(100)) //在指定时间执行完成就返回true
{
Console.Write(\”.\”);
}
Console.WriteLine(mytask.Result);//task任务取消，所以获取task.Result会报错

Task taskFactory = Task.Factory.StartNew(() =>
{
Thread.Sleep(1000);
Console.WriteLine(\”perfect!\”);
});
Console.WriteLine(taskFactory.Status);
taskFactory.Wait();//taskFactory任务完成才往下执行
Task.WaitAll(mytask, taskFactory);//所有任务完成再往下执行
Task.WaitAny(mytask, taskFactory);//任一任务完成就往下执行
Console.WriteLine(taskFactory.Status);

Task taskTest = taskFactory.ContinueWith(DoOnSecond);//ContinueWith用法举例
}
static void DoOnSecond(Task t)
{
Console.WriteLine(\”task {0} finished\”, t.Id);
Console.WriteLine(\”this task id {0}\”, Task.CurrentId);
Console.WriteLine(\”do some cleanup\”);
}
#endregion

原文链接：https://blog.csdn.net/DotnetNb/article/details/129000803