Task.Factory.StartNew (() =>
    {
        Console.WriteLine("Hello word!");
    });

    Task task = 
    new Task
    (() =>
    {
        Console.WriteLine("Hello,Word!");
    });
    task.Start();

public Task(Action action);
public Task(Action<object> action, 
object state
);給action傳參數(shù)
public Task(Action action, CancellationToken cancellationToken);
public Task(Action action, TaskCreationOptions creationOptions);

Task task2 = new Task((obj ) => 
{
    Console.WriteLine("Message: {0}", obj); }, "Say \"Hello\" from task2");
    task2.Start();
}

    var loop = 0;
    var task1 = new Task<int>(() => 
    {
        for (var i = 0; i < 1000; i++)
            loop += i;
        return loop;
    });
    task1.Start();           
    var loopResut = task1.Result;
 
    var task2 = new Task<long>(obj=>
    {
        long res = 0;
        var looptimes = (int)obj;
        for (var i = 0; i < looptimes; i++)
            res += i;
        return res;
    },loopResut);
     
    task2.Start();
    var resultTask2 = task2.Result;
 
    Console.WriteLine("任務(wù)1的結(jié)果':{0}\n任務(wù)2的結(jié)果:{1}",   loopResut,resultTask2);

    var ReceiveTask  = new Task(() => ReceiveXml());
    var ResolveTask = ReceiveTask .ContinueWith <bool>((r) => ResolveXml());
    var SendFeedBackTask = ResolveTask.ContinueWith <string>((s) => SendFeedBack(s.Result));
    ReceiveTask.Start();
    Console.WriteLine(SendFeedBackTask.Result);

   var SendFeedBackTask = Task.Factory.StartNew(() => ReceiveXml())
        .ContinueWith<bool>(s => ResolveXml())
        .ContinueWith<string>(r => SendFeedBack(r.Result));
    Console.WriteLine(SendFeedBackTask.Result);

Task t5 = t1.ContinueWith(DoOnError,
TaskContinuationOptions.OnlyOnFaulted);

var outTask = Task.Factory.StartNew(() =>
{
    Console.WriteLine("Outer task beginning...");
    var childTask = Task.Factory.StartNew(() =>
    {
        Thread.SpinWait(3000000);
        Console.WriteLine("Detached nested task completed.");
    });
});
outTask.Wait();
Console.WriteLine("Outer task completed.");
Console.ReadKey();

var outTask = Task.Factory.StartNew(() =>
{
    Console.WriteLine("Outer task beginning...");
    var childTask = Task.Factory.StartNew(() =>
    {
        Thread.SpinWait(3000000);
        Console.WriteLine("Detached nested task completed.");
    },TaskCreationOptions.AttachedToParent);
});
outTask.Wait();
Console.WriteLine("Outer task completed.");

var cts = new CancellationTokenSource();

var ct =  cts.Token;

var task = Task.Factory.StartNew(() =>
{
    for (var i = 0; i < 10000000; i++)
    {
        if (ct.IsCancellationRequested)
        {
            Console.WriteLine("任務(wù)開始取消...");
            throw new OperationCanceledException(ct);
        }
         //或者直接在檢測到異常時(shí)，扔出異常：  token.ThrowIfCancellationRequested();
         //或者等待 WaitHandle：           token.WaitHandle.WaitOne();


    }
},ct);//傳入CancellationToken作為Task第二個(gè)參數(shù)

ct.Register(() =>
{
    Console.WriteLine("已經(jīng)取消");
});

Thread.Sleep(5000);
cts.Cancel();//如果想要取消一個(gè)Task的運(yùn)行，只要調(diào)用CancellationToken實(shí)例的Cancel()方法就可以了。

try
{
    task.Wait();
}
catch (AggregateException e)
{
    foreach (var v in e.InnerExceptions)
        Console.WriteLine("msg: " + v.Message);
}

    var cts = new CancellationTokenSource();
    var ct = cts.Token;
 
    var task = new Task(() =>
    {
        for (var i = 0; i < 100000; i++)
        {
            var cancelled = ct.WaitHandle.WaitOne(1000 );
            Console.WriteLine(" {0}. Cancelled? {1}", i, cancelled);
            if (cancelled)
            {
                throw new OperationCanceledException(ct);
            }
        }
    }, ct);
    task.Start();

            var task = new Task(() =>
            {
                for (var i = 0; i < 100000; i++)
                {
                    Thread.Sleep(10000);
                    var cancelled =ct.IsCancellationRequested;
                    Console.WriteLine(" {0}. Cancelled? {1}",
                                i, cancelled); if (cancelled)
                    {
                        throw new OperationCanceledException(ct);
                    }
                }
            },ct);

static void Main(string[] args)
{
    var tokenSource = new CancellationTokenSource();
    CancellationToken token = tokenSource.Token;
        Task task = createTask(token,6);    task.Start();
    Console.WriteLine("Wait() complete.");
    task.Wait();
    Console.WriteLine("Task Completed.");
    
    task = createTask(token,3);
    task.Start();
    Console.WriteLine("Wait(2) secs for task to complete.");
    bool completed = task.Wait(2000);
    Console.WriteLine("Wait ended - task completed: {0}", completed);
    
    task = createTask(token,4);
    task.Start();
    Console.WriteLine("Wait(2,token) for task to complete.");
    completed = task.Wait(2000, token);
    Console.WriteLine("Wait ended - task completed: {0} task cancelled {1}",
    completed, task.IsCanceled);
    Console.WriteLine("Main method complete. Press enter to finish.");
    Console.ReadLine();
}
static Task createTask(CancellationToken token,int loop)
{
    return new Task(() =>
    {
        for (int i = 0; i < loop; i++)
        {
            token.ThrowIfCancellationRequested();
            Console.WriteLine("Task - Int value {0}", i);
            token.WaitHandle.WaitOne(1000);
        }
    }, token);
}

   var tokenSource = new CancellationTokenSource();
    CancellationToken token = tokenSource.Token;
    var task1 = createTask(token,2);
    var task2 = createTask(token, 5);
    task1.Start();
    task2.Start();
    Console.WriteLine("Waiting for tasks to complete.");
    Task.WaitAll(task1, task2);
    Console.WriteLine("Tasks Completed.");

ConcurrentStack<int> stack = new ConcurrentStack<int>();

//t1先執(zhí)行
var t1 = Task.Factory.StartNew(() =>
{
    stack.Push(1);
    stack.Push(2);
});

//t2,t3并行執(zhí)行
var t2 = t1.
ContinueWith
(t =>
{
    int result;

    stack.TryPop(out result);
});

//t2,t3并行執(zhí)行
var t3 = t1.
ContinueWith
(t =>
{
    int result;

    stack.TryPop(out result);
});

//等待t2和t3執(zhí)行完
Task.WaitAll(t2, t3);

 //t4z再執(zhí)行
var t4 = Task.Factory.StartNew(() =>
{
    Console.WriteLine("當(dāng)前集合元素個(gè)數(shù)：" + stack.Count);
});

    var tokenSource = new CancellationTokenSource();
    CancellationToken token = tokenSource.Token;
    var task1 = createTask(token,2);
    var task2 = createTask(token, 5);
    task1.Start();
    task2.Start();
    Console.WriteLine("Waiting for tasks to complete.");
    var index = Task.WaitAny(task1, task2);
    Console.WriteLine("Tasks Completed.Index is {0}",index);

var tokenSource = new CancellationTokenSource();
    var token = tokenSource.Token;
    var task1 = new Task(() =>
    {
        throw new NullReferenceException() { 
Source
="task1"};
    });
    var task2 = new Task(() =>
    {
        throw new ArgumentNullException("a", "a para can not be null") { Source="task2"};
    });
    task1.Start(); task2.Start(); 
    try
    {
        Task.WaitAll(task1, task2);
    }
    catch(AggregateException ex)
    {
        foreach (Exception inner in ex.InnerExceptions)
        {
            Console.WriteLine("Exception type {0} from {1}",
            inner.GetType(), inner.Source);
        }
    }

    try
    {
        Task.WaitAll(task1, task2, task3, task4);
    }
    catch(AggregateException ex)
    {
        ex.Handle((e) =>
        {
            if (e is OperationCanceledException)
            {
                return true;
            }
            else
            {
                return false;
            }
        });
    }

            // do the same thing in a single statement
            Lazy<Task<string>> lazyData2 = new Lazy<Task<string>>(
            () => Task<string>.Factory.StartNew(() =>
            {
                Console.WriteLine("Task body working...");
                return "Task Result";
            }));

            Console.WriteLine("Calling second lazy variable");
            Console.WriteLine("Result from task: {0}", lazyData2.Value.Result);