Thread pools are often employed in server applications. Each incoming request is assigned to a thread from the thread pool, so the request can be processed asynchronously, without tying up the primary thread or delaying the processing of subsequent requests.

Thread pools typically have a maximum number of threads. If all the threads are busy, additional tasks are placed in queue until they can be serviced as threads become available.

Here I am giving an example of ThreadPool class.  Let’s see the brief demonstration of example.

Example:

using System.Threading;
using System.Diagnostics;
  
namespace PoolThread
{
     class MyProcess
    {
         public ManualResetEventdoneEvent;
 
         publicMyProcess(ManualResetEvent sendEvent)
         {
         // Assign notify event from ThreadPool 
          this.doneEvent=sendEvent;
         }
 
        public void MyProcessThreadPoolCallback(Objectindex)
         {
             int threadIndex= (int)index;
          Console.WriteLine("thread {0} started...", threadIndex);
         // Call the process that is created on every thread
         StartProcess();
          Console.WriteLine("thread {0} end...", threadIndex);
 
         // Indicates that the process has been completed
          this.doneEvent.Set();
         }
 
// Start any process 
     public void StartProcess()
     {
         // Start process that open c:\ directory 
          Process.Start("C:\\");
      }
   
 }
 
public class ThreadPoolExample
 {
      static voidMain()
     {
          const inttotalCountProcess=10;
          // Create manualresetevent array to assign with process
          ManualResetEvent[]  sendEvents= new ManualResetEvent[totalCountProcess];
          // Create MyProcess objects array 
          MyProcess[]  MyProcessArray=new MyProcess[totalCountProcess];
       
          // Configure and launch threads using ThreadPool:
          Console.WriteLine("launching thread...");
          for (inti=0; i<totalCountProcess ; i++)
         {
             sendEvents[i] = new ManualResetEvent(false);
              MyProcess p= newMyProcess(sendEvents[i]);
             MyProcessArray[i] =p;
              // ThreadPool call QueueUserWorkItem method to execute when ThreadPool having thread
              ThreadPool.QueueUserWorkItem(p.MyProcessThreadPoolCallback, i);
              // After execute one thread it go in sleep mode for 2 second 
              Thread.Sleep(2000);
         }
          // Wait for all thread to complete execution 
          WaitHandle.WaitAll(sendEvents);
          Console.WriteLine("All process are complete.");
         Console.ReadKey();
 
           }
 
    }
}

Desired Output: