Example of C# multithreading waiting for all child threads to end

 //In the process of using multi-threading, you may encounter in some cases that you have to wait until all the child threads are executed before the main thread will proceed to the next step. The method is as follows      List<ManualResetEvent> manualEvents = new List<ManualResetEvent>();//Create thread waiting for collection      for (int i = 0; i < 64; i++) //The number of WaitHandles must be less than or equal to 64, so the maximum number of threads is 64      {
        MB m = new MB();//Custom class, used to pass parameters        = new ManualResetEvent(false);
         = i;

        ();
        (ThreadMethod, m);
      }
      (());//Waiting for all threads to end      ("Thread Finished!");

private static void ThreadMethod(object obj)
    {
      MB m = (MB)obj;
      (1000);//Wait for 1 second to simulate the system handling things      ();//Set the event to terminate      ("Thread execute:" + );
    }

        using (var countdown = new MutipleThreadResetEvent())
        {
          for (int i = 0; i < ; i++)
          {
            //Open N threads and pass the MutipleThreadResetEvent object to the child thread            Param p = new Param();
             = countdown;
             = pa[i];
            (MyHttpRequest, p);
          }

          //Waiting for all threads to complete execution          ();
        }

public class MutipleThreadResetEvent: IDisposable
  {
    private readonly ManualResetEvent done;
    private readonly int total;
    private long current;

    /// <summary>
    /// Constructor    /// </summary>
    /// <param name="total">Total number of threads to wait for execution</param>    public MutipleThreadResetEvent(int total)
    {
       = total;
      current = total;
      done = new ManualResetEvent(false);
    }

    /// &lt;summary&gt;
    /// Wake up a waiting thread    /// &lt;/summary&gt;
    public void SetOne()
    {
      // Interlocked atomic operation class, here to reduce the counter by 1      if ((ref current) == 0)
      {
        //When the waiting thread is completed, wake up the waiting thread        ();
      }
    }

    /// &lt;summary&gt;
    /// Wait for so the thread is executed    /// &lt;/summary&gt;
    public void WaitAll()
    {
      ();
    }

    /// &lt;summary&gt;
    /// Free up space occupied by the object    /// &lt;/summary&gt;
    public void Dispose()
    {
      ((IDisposable)done).Dispose();
    }
  }