Thread::Interrupt Method ()

 

Interrupts a thread that is in the WaitSleepJoin thread state.

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

public:
[SecurityPermissionAttribute(SecurityAction::Demand, ControlThread = true)]
void Interrupt()

Exception Condition
SecurityException

The caller does not have the appropriate SecurityPermission.

If this thread is not currently blocked in a wait, sleep, or join state, it will be interrupted when it next begins to block.

ThreadInterruptedException is thrown in the interrupted thread, but not until the thread blocks. If the thread never blocks, the exception is never thrown, and thus the thread might complete without ever being interrupted.

The following code example shows the behavior of a running thread when it is interrupted and subsequently gets blocked.

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();
}

SecurityPermission

for advanced operations on threads. Associated enumeration: SecurityPermissionFlag::ControlThread.

.NET Framework
Available since 1.1
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