Question

I have created threads dynamically.

static void Main(string[] args)
{

    int ThreadCount =Convert.ToInt32ConfigurationManager.AppSettings["Threads"]);
    List<Thread> th = new List<Thread>();
    for (int i = 0; i < ThreadCount; i++)
    {
      Thread t = new Thread(print);
      th.Add(t);
    }
    foreach (Thread t in th)
    {
       t.Start();
    }
 }
 public static void print()
 {
    console.writeline("123");
 }

I want to know when this threads will complete.
On completion of these threads I want to print a message of “DONE”

How can I do this.

Answer 1

Thread.Join() could help; see http://msdn.microsoft.com/en-us/library/95hbf2ta.aspx.

foreach (var t in th)
   t.Join();

Console.WriteLine("DONE");

You might want to look at the higher level TPL (Task Parallel Library) API; see http://msdn.microsoft.com/en-us/library/dd537609.aspx. It could be easier to use in the long run.

var tasks[] = new Task[n];
for (int i = 0; i < n; ++i)
{
   tasks[i] = new Task(() => Console.WriteLine(123));
   tasks[i].Start();
}

Tasks.WaitAll(tasks);
Console.WriteLine("DONE");

Or in PLINQ , http://msdn.microsoft.com/en-us/library/dd460688.aspx, (haven’t compiled the code)

Parallel.ForEach(Enumerable.Range(1, n), i => Console.WriteLine(i));
Console.WriteLine("DONE");