可以參見 WaitHandle.WaitAll 方法。

WaitHandle的名稱空間是System.Thread。

可以為每一個執行緒建立一個

WaitHandle，比如：

WaitHandle[] waitHandles = new WaitHandle[]

{

new AutoResetEvent(false),

new AutoResetEvent(false),

...

};

然後在每條執行緒結束時，set與之相對應的那個 WaitHandle，

在主執行緒中，使用

WaitHandle.WaitAll方法來等待所有的WaitHandle，

比如：

WaitHandle.WaitAll(waitHandles);

以下是MSDN中的示例程式碼：

using System;

using System.Threading;

public sealed class App

{

// Define an array with two AutoResetEvent WaitHandles.

static WaitHandle[] waitHandles = new WaitHandle[]

{

new AutoResetEvent(false),

new AutoResetEvent(false)

};

// Define a random number generator for testing.

static Random r = new Random();

static void Main()

{

// Queue up two tasks on two different threads;

// wait until all tasks are completed.

DateTime dt = DateTime.Now;

Console.WriteLine("Main thread is waiting for BOTH tasks to complete.");

ThreadPool.QueueUserWorkItem(new WaitCallback(DoTask), waitHandles[0]);

ThreadPool.QueueUserWorkItem(new WaitCallback(DoTask), waitHandles[1]);

WaitHandle.WaitAll(waitHandles);

// The time shown below should match the longest task.

Console.WriteLine("Both tasks are completed (time waited={0})",

(DateTime.Now - dt).TotalMilliseconds);

// Queue up two tasks on two different threads;

// wait until any tasks are completed.

dt = DateTime.Now;

Console.WriteLine();

Console.WriteLine("The main thread is waiting for either task to complete.");

ThreadPool.QueueUserWorkItem(new WaitCallback(DoTask), waitHandles[0]);

ThreadPool.QueueUserWorkItem(new WaitCallback(DoTask), waitHandles[1]);

int index = WaitHandle.WaitAny(waitHandles);

// The time shown below should match the shortest task.

Console.WriteLine("Task {0} finished first (time waited={1}).",

index + 1, (DateTime.Now - dt).TotalMilliseconds);

}

static void DoTask(Object state)

{

AutoResetEvent are = (AutoResetEvent) state;

int time = 1000 * r.Next(2, 10);

Console.WriteLine("Performing a task for {0} milliseconds.", time);

Thread.Sleep(time);

are.Set();

}

}

// This code produces output similar to the following:

//

// Main thread is waiting for BOTH tasks to complete.

// Performing a task for 7000 milliseconds.

// Performing a task for 4000 milliseconds.

// Both tasks are completed (time waited=7064.8052)

//

// The main thread is waiting for either task to complete.

// Performing a task for 2000 milliseconds.

// Performing a task for 2000 milliseconds.

// Task 1 finished first (time waited=2000.6528).