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Thread.Start Method

Causes the operating system to change the state of the current instance to ThreadState.Running.

Namespace:  System.Threading
Assembly:  mscorlib (in mscorlib.dll)

[HostProtectionAttribute(SecurityAction.LinkDemand, Synchronization = true, 
	ExternalThreading = true)]
public void Start()

ExceptionCondition
ThreadStateException

The thread has already been started.

OutOfMemoryException

There is not enough memory available to start this thread.

NoteNote:

The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: Synchronization | ExternalThreading. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

Once a thread is in the ThreadState.Running state, the operating system can schedule it for execution. The thread begins executing at the first line of the method represented by the ThreadStart or ParameterizedThreadStart delegate supplied to the thread constructor.

NoteNote:

If this overload is used with a thread created using a ParameterizedThreadStart delegate, null is passed to the method executed by the thread.

Once the thread terminates, it cannot be restarted with another call to Start.

The following code example demonstrates creating a thread and starting it.

This code produces the following output:

     In main.
     Working thread...
     In main. Working thread...
     In main.
     Working thread...

Note that the sequence of the output statements is typical, but is not guaranteed to be identical across systems.

Thread procedures can be static methods or instance methods. See the code example provided for the ThreadStart delegate. For more information about thread creation, see Creating Threads and Passing Data at Start Time.

using System;
using System.Threading;

public class ThreadWork 
{
   public static void DoWork()
   {
      for(int i = 0; i<3;i++)
      {
         Console.WriteLine("Working thread...");
            Thread.Sleep(100);
      }
   }
}
class ThreadTest
{
   public static void Main()
   {
      ThreadStart myThreadDelegate = new ThreadStart(ThreadWork.DoWork);
      Thread myThread = new Thread(myThreadDelegate);
      myThread.Start();
         for(int i = 0; i<3; i++)
         {
         Console.WriteLine("In main.");
            Thread.Sleep(100);
         }
   }
}

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0
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