Timeout Class (System.Threading)

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.NET Framework Class Library
Timeout Class

Contains a constant used to specify an infinite amount of time. This class cannot be inherited.

Inheritance Hierarchy

System.Object
  System.Threading.Timeout

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

Visual Basic
<ComVisibleAttribute(True)> _
Public NotInheritable Class Timeout
C#
[ComVisibleAttribute(true)]
public static class Timeout
Visual C++
[ComVisibleAttribute(true)]
public ref class Timeout abstract sealed
F#
[<AbstractClass>]
[<Sealed>]
[<ComVisibleAttribute(true)>]
type Timeout =  class end

The Timeout type exposes the following members.

Methods

  Name Description
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Fields

  Name Description
Public field Static member Supported by the XNA Framework Infinite A constant used to specify an infinite waiting period. This field is constant.
Top
Remarks

The only member of this class, Infinite, is a constant used by methods that accept an integer timeout parameter, such as Thread.Sleep(Int32), Thread.Join(Int32), and ReaderWriterLock.AcquireReaderLock(Int32).

Examples

The following code example shows a thread going to sleep for an infinite time and subsequently being woken up.

Visual Basic

Option Explicit
Option Strict

Imports System
Imports System.Security.Permissions
Imports System.Threading

Public Class ThreadInterrupt

    <MTAThread> _
    Shared Sub Main()
        Dim stayAwake As New StayAwake()
        Dim newThread As New Thread(AddressOf stayAwake.ThreadMethod)
        newThread.Start()

        ' The following line causes an exception to be thrown 
        ' in ThreadMethod if newThread is currently blocked
        ' or becomes blocked in the future.
        newThread.Interrupt()
        Console.WriteLine("Main thread calls Interrupt on newThread.")

        ' Tell newThread to go to sleep.
        stayAwake.SleepSwitch = True

        ' Wait for newThread to end.
        newThread.Join()
    End Sub

End Class

Public Class StayAwake

    Dim sleepSwitchValue As Boolean = False

    WriteOnly Property SleepSwitch As Boolean
        Set
            sleepSwitchValue = Value
        End Set
    End Property 

    Sub New()
    End Sub

    Sub ThreadMethod()
        Console.WriteLine("newThread is executing ThreadMethod.")
        While Not sleepSwitchValue

            ' Use SpinWait instead of Sleep to demonstrate the 
            ' effect of calling Interrupt on a running thread.
            Thread.SpinWait(10000000)
        End While
        Try
            Console.WriteLine("newThread going to sleep.")

            ' When newThread goes to sleep, it is immediately 
            ' woken up by a ThreadInterruptedException.
            Thread.Sleep(Timeout.Infinite)
        Catch ex As ThreadInterruptedException
            Console.WriteLine("newThread cannot go to " & _
                "sleep - interrupted by main thread.")
        End Try
    End Sub

End Class


C#

using System;
using System.Security.Permissions;
using System.Threading;

class ThreadInterrupt
{
    static void Main()
    {
        StayAwake stayAwake = new StayAwake();
        Thread newThread = 
            new Thread(new ThreadStart(stayAwake.ThreadMethod));
        newThread.Start();

        // The following line causes an exception to be thrown 
        // in ThreadMethod if newThread is currently blocked
        // or becomes blocked in the future.
        newThread.Interrupt();
        Console.WriteLine("Main thread calls Interrupt on newThread.");

        // Tell newThread to go to sleep.
        stayAwake.SleepSwitch = true;

        // Wait for newThread to end.
        newThread.Join();
    }
}

class StayAwake
{
    bool sleepSwitch = false;

    public bool SleepSwitch
    {
        set{ sleepSwitch = value; }
    }

    public StayAwake(){}

    public void ThreadMethod()
    {
        Console.WriteLine("newThread is executing ThreadMethod.");
        while(!sleepSwitch)
        {
            // Use SpinWait instead of Sleep to demonstrate the 
            // effect of calling Interrupt on a running thread.
            Thread.SpinWait(10000000);
        }
        try
        {
            Console.WriteLine("newThread going to sleep.");

            // When newThread goes to sleep, it is immediately 
            // woken up by a ThreadInterruptedException.
            Thread.Sleep(Timeout.Infinite);
        }
        catch(ThreadInterruptedException e)
        {
            Console.WriteLine("newThread cannot go to sleep - " +
                "interrupted by main thread.");
        }
    }
}


Visual C++

using namespace System;
using namespace System::Security::Permissions;
using namespace System::Threading;

ref class StayAwake
{
private:
   bool sleepSwitch;

public:

   property bool SleepSwitch 
   {
      void set( bool value )
      {
         sleepSwitch = value;
      }

   }
   StayAwake()
   {
      sleepSwitch = false;
   }

   void ThreadMethod()
   {
      Console::WriteLine( "newThread is executing ThreadMethod." );
      while (  !sleepSwitch )
      {

         // Use SpinWait instead of Sleep to demonstrate the 
         // effect of calling Interrupt on a running thread.
         Thread::SpinWait( 10000000 );
      }

      try
      {
         Console::WriteLine( "newThread going to sleep." );

         // When newThread goes to sleep, it is immediately 
         // woken up by a ThreadInterruptedException.
         Thread::Sleep( Timeout::Infinite );
      }
      catch ( ThreadInterruptedException^ /*e*/ ) 
      {
         Console::WriteLine( "newThread cannot go to sleep - "
         "interrupted by main thread." );
      }

   }

};

int main()
{
   StayAwake^ stayAwake = gcnew StayAwake;
   Thread^ newThread = gcnew Thread( gcnew ThreadStart( stayAwake, &StayAwake::ThreadMethod ) );
   newThread->Start();

   // The following line causes an exception to be thrown 
   // in ThreadMethod if newThread is currently blocked
   // or becomes blocked in the future.
   newThread->Interrupt();
   Console::WriteLine( "Main thread calls Interrupt on newThread." );

   // Then tell newThread to go to sleep.
   stayAwake->SleepSwitch = true;

   // Wait for newThread to end.
   newThread->Join();
}



Version Information

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1
Platforms

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Thread Safety

This type is thread safe.

See Also

Reference

Other Resources