Thread.CurrentThread Thread.CurrentThread Thread.CurrentThread Thread.CurrentThread Property

Definition

Gets the currently running thread.

public:
 static property System::Threading::Thread ^ CurrentThread { System::Threading::Thread ^ get(); };
public static System.Threading.Thread CurrentThread { get; }
member this.CurrentThread : System.Threading.Thread
Public Shared ReadOnly Property CurrentThread As Thread
Property Value

A Thread that is the representation of the currently running thread.

Examples

The following example creates a task that in turn creates 20 child tasks. The application itself, as well as each task, calls the ShowThreadInformation method, which uses the CurrentThread property to display information about the thread on which it is running.

using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;

public class Example
{
   private static Object lockObj = new Object();
   private static Object rndLock = new Object();

   public static void Main()
   {
      Random rnd = new Random();
      var tasks = new List<Task<Double>>();
      ShowThreadInformation("Application");

      Task<Double> t = Task.Run( () => { ShowThreadInformation("Main Task(Task #" + Task.CurrentId.ToString() + ")");
                                         for (int ctr = 1; ctr <= 20; ctr++)
                                           tasks.Add(Task.Factory.StartNew(
                                              () => { ShowThreadInformation("Task #" + Task.CurrentId.ToString());
                                                      long s = 0;
                                                      for (int n = 0; n <= 999999; n++) {
                                                         lock (rndLock) {
                                                            s += rnd.Next(1, 1000001);
                                                         }
                                                      }
                                                      return s/1000000.0;
                                                    } ));

                                        Task.WaitAll(tasks.ToArray());
                                        Double grandTotal = 0;
                                        Console.WriteLine("Means of each task: ");
                                        foreach (var child in tasks) {
                                           Console.WriteLine("   {0}", child.Result);
                                           grandTotal += child.Result;
                                        }
                                        Console.WriteLine();
                                        return grandTotal / 20;
                                   } );
      Console.WriteLine("Mean of Means: {0}", t.Result);
   }

  private static void ShowThreadInformation(String taskName)
  {
      String msg = null;
      Thread thread = Thread.CurrentThread;
      lock(lockObj) {
         msg = String.Format("{0} thread information\n", taskName) +
               String.Format("   Background: {0}\n", thread.IsBackground) +
               String.Format("   Thread Pool: {0}\n", thread.IsThreadPoolThread) +
               String.Format("   Thread ID: {0}\n", thread.ManagedThreadId);
      }
      Console.WriteLine(msg);
   }
}
// The example displays output like the following:
//       Application thread information
//          Background: False
//          Thread Pool: False
//          Thread ID: 1
//
//       Main Task(Task #1) thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 3
//
//       Task #2 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 4
//
//       Task #4 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 10
//
//       Task #3 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 9
//
//       Task #5 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 3
//
//       Task #7 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 5
//
//       Task #6 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 7
//
//       Task #8 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 6
//
//       Task #9 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 8
//
//       Task #10 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 9
//
//       Task #11 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 10
//
//       Task #12 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 6
//
//       Task #13 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 4
//
//       Task #14 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 3
//
//       Task #15 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 7
//
//       Task #16 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 5
//
//       Task #17 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 8
//
//       Task #18 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 9
//
//       Task #19 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 10
//
//       Task #20 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 4
//
//       Task #21 thread information
//          Background: True
//          Thread Pool: True
//          Thread ID: 7
//
//       Means of each task:
//          500038.740584
//          499810.422703
//          500217.558077
//          499868.534688
//          499295.505866
//          499893.475772
//          499601.454469
//          499828.532502
//          499606.183978
//          499700.276056
//          500415.894952
//          500005.874751
//          500042.237016
//          500092.764753
//          499998.798267
//          499623.054718
//          500018.784823
//          500286.865993
//          500052.68285
//          499764.363303
//
//       Mean of Means: 499908.10030605
Imports System.Collections.Generic
Imports System.Threading
Imports System.Threading.Tasks

Module Example
   Private lockObj As New Object()
   Private rndLock As New Object()
   
   Public Sub Main()
      Dim rnd As New Random()
      Dim tasks As New List(Of Task)
      ShowThreadInformation("Application")

      Dim t As Task(Of Double) = Task.Run( Function()
                                        ShowThreadInformation("Main Task(Task #" + Task.CurrentId.ToString() + ")")
                                        For ctr As Integer = 1 To 20
                                           tasks.Add(Task.Factory.StartNew( Function()
                                                                     ShowThreadInformation("Task #" + Task.CurrentId.ToString())
                                                                     Dim s As Long = 0
                                                                     For n As Integer = 0 To 999999
                                                                        SyncLock rndLock
                                                                           s += rnd.Next(1, 1000001)
                                                                        End SyncLock
                                                                     Next
                                                                     Return s/1000000
                                                                  End Function))
                                        Next

                                        Task.WaitAll(tasks.ToArray())
                                        Dim grandTotal As Double
                                        Console.WriteLine("Means of each task: ")
                                        For Each t In tasks
                                           Console.WriteLine("   {0}", t.Result)
                                           grandTotal += t.Result
                                        Next
                                        Console.WriteLine()
                                        Return grandTotal / 20
                                   End Function )
      Console.WriteLine("Mean of Means: {0}", t.Result)
   End Sub
   
   Private Sub ShowThreadInformation(taskName As String)
      Dim msg As String = Nothing
      Dim thread As Thread = Thread.CurrentThread
      SyncLock lockObj
         msg = String.Format("{0} thread information", taskName) + vbCrLf +
               String.Format("   Background: {0}", thread.IsBackground) + vbCrLf +
               String.Format("   Thread Pool: {0}", thread.IsThreadPoolThread) + vbCrLf +
               String.Format("   Thread ID: {0}", thread.ManagedThreadId) + vbCrLf
      End SyncLock
      Console.WriteLine(msg)
   End Sub
End Module
' The example displays output like the following:
'       Application thread information
'          Background: False
'          Thread Pool: False
'          Thread ID: 1
'
'       Main Task(Task #1) thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 3
'
'       Task #2 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 4
'
'       Task #4 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 10
'
'       Task #3 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 9
'
'       Task #5 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 3
'
'       Task #7 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 5
'
'       Task #6 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 7
'
'       Task #8 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 6
'
'       Task #9 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 8
'
'       Task #10 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 9
'
'       Task #11 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 10
'
'       Task #12 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 6
'
'       Task #13 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 4
'
'       Task #14 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 3
'
'       Task #15 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 7
'
'       Task #16 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 5
'
'       Task #17 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 8
'
'       Task #18 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 9
'
'       Task #19 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 10
'
'       Task #20 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 4
'
'       Task #21 thread information
'          Background: True
'          Thread Pool: True
'          Thread ID: 7
'
'       Means of each task:
'          500038.740584
'          499810.422703
'          500217.558077
'          499868.534688
'          499295.505866
'          499893.475772
'          499601.454469
'          499828.532502
'          499606.183978
'          499700.276056
'          500415.894952
'          500005.874751
'          500042.237016
'          500092.764753
'          499998.798267
'          499623.054718
'          500018.784823
'          500286.865993
'          500052.68285
'          499764.363303
'
'       Mean of Means: 499908.10030605/

Each child task generates 1 million random numbers between 1 and 1 million and returns their mean. The parent task calls the Task.WaitAll method to ensure that the child tasks have completed before displaying the mean returned by each task and calculating the mean of means.

Note that while the application runs on a foreground thread, each task runs on a thread pool thread.

Applies to