Thread.CurrentThread Property
Definition
Important
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Gets the currently running thread.
public:
static property System::Threading::Thread ^ CurrentThread { System::Threading::Thread ^ get(); };public static System.Threading.Thread CurrentThread { get; }static member CurrentThread : System.Threading.ThreadPublic Shared ReadOnly Property CurrentThread As ThreadProperty 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
open System
open System.Threading
open System.Threading.Tasks
let lockObj = obj ()
let rndLock = obj ()
let showThreadInformation taskName =
let thread = Thread.CurrentThread
lock lockObj (fun () ->
printfn
$"{taskName} thread information\n Background: {thread.IsBackground}\n Thread Pool: {thread.IsThreadPoolThread}\n Thread ID: {thread.ManagedThreadId}\n")
let rnd = Random()
showThreadInformation "Application"
let t =
Task.Run(fun () ->
showThreadInformation $"Main Task(Task #{Task.CurrentId})"
let tasks =
[| for _ = 1 to 20 do
Task.Factory.StartNew(fun () ->
showThreadInformation $"Task #{Task.CurrentId}"
let mutable s = 0L
for n = 0 to 999999 do
lock rndLock (fun () -> s <- s + (rnd.Next(1, 1000001) |> int64))
float s / 1000000.) |]
Task.WaitAll(box tasks :?> Task[])
let mutable grandTotal = 0.
printfn "Means of each task: "
for child in tasks do
printfn $" {child.Result}"
grandTotal <- grandTotal + child.Result
printfn ""
grandTotal / 20.)
printfn $"Mean of Means: {t.Result}"
// 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
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