当所有线程完成时

这是我第一次真正尝试使用多线程，我想知道如何判断所有任务组何时完成运行：

for (int i = 0; i < taskGroups.Count(); i++) {
    ThreadStart t = delegate { RunThread(taskGroups[i]); };
    new Thread(t).Start();
}
if(allThreadsComplete){ //???

}

任何帮助将非常感激

附录：

ThreadStart[] threads = new ThreadStart[taskGroups.Count()];
for (int i = 0; i < taskGroups.Count(); i++) {
    threads[i] = new ThreadStart[]
    threads[i] = delegate { RunThread(taskGroups[i]); };
    new Thread(t).Start();
}
bool threadsComplete = false;
while(!threadsComplete){
    for(int i=0;i<taskGroups.Count();i++){
        if(threads[i].State == complete)
        threadsComplete = true;
    }
}

您需要存储所有线程，然后调用 Thread.Join()。

像这样的东西：

List<Thread> threads = new List<Thread>();
for (int i = 0; i < taskGroups.Count(); i++) {
   int temp = i; //This fixes the issue with i being shared
   Thread thread = new Thread(() => RunThread(taskGroups[temp]));
   threads.Add(thread);
   thread.Start();
}

foreach (var thread in threads) {
    thread.Join();
}