ReaderWriterLock.ReleaseReaderLock Methode

  • Referenz

Definition

Namespace:
System.Threading
Assembly:
System.Threading.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll

Verringert die Sperrenanzahl.

public:
 void ReleaseReaderLock();
public void ReleaseReaderLock ();
member this.ReleaseReaderLock : unit -> unit
Public Sub ReleaseReaderLock ()

Ausnahmen

ApplicationException

Der Thread verfügt weder über Lese- noch über Schreibsperren.

Beispiele

Im folgenden Codebeispiel wird gezeigt, wie Sie eine Lesesperre erwerben und freigeben und wie sie die Ausnahme behandeln, die ausgelöst wird, wenn sich eine Anforderung ausdauert.

Dieser Code ist Teil eines größeren Beispiels, das für die ReaderWriterLock Klasse bereitgestellt wird.

// The complete code is located in the ReaderWriterLock
// class topic.
using namespace System;
using namespace System::Threading;
public ref class Test
{
public:

   // Declaring the ReaderWriterLock at the class level
   // makes it visible to all threads.
   static ReaderWriterLock^ rwl = gcnew ReaderWriterLock;

   // For this example, the shared resource protected by the
   // ReaderWriterLock is just an integer.
   static int resource = 0;

// The complete code is located in the ReaderWriterLock class topic.
using System;
using System.Threading;

public class Example
{
   static ReaderWriterLock rwl = new ReaderWriterLock();
   // Define the shared resource protected by the ReaderWriterLock.
   static int resource = 0;

' The complete code is located in the ReaderWriterLock class topic.
Imports System.Threading

Public Module Example
   Private rwl As New ReaderWriterLock()
   ' Define the shared resource protected by the ReaderWriterLock.
   Private resource As Integer = 0

// Shows how to request and release a reader lock, and
// how to handle time-outs.
static void ReadFromResource( int timeOut )
{
   try
   {
      rwl->AcquireReaderLock( timeOut );
      try
      {

         // It is safe for this thread to read from
         // the shared resource.
         Display( String::Format( "reads resource value {0}", resource ) );
         Interlocked::Increment( reads );
      }
      finally
      {

         // Ensure that the lock is released.
         rwl->ReleaseReaderLock();
      }

   }
   catch ( ApplicationException^ )
   {

      // The reader lock request timed out.
      Interlocked::Increment( readerTimeouts );
   }

}

// Request and release a reader lock, and handle time-outs.
static void ReadFromResource(int timeOut)
{
   try {
      rwl.AcquireReaderLock(timeOut);
      try {
         // It is safe for this thread to read from the shared resource.
         Display("reads resource value " + resource);
         Interlocked.Increment(ref reads);
      }
      finally {
         // Ensure that the lock is released.
         rwl.ReleaseReaderLock();
      }
   }
   catch (ApplicationException) {
      // The reader lock request timed out.
      Interlocked.Increment(ref readerTimeouts);
   }
}

' Request and release a reader lock, and handle time-outs.
Sub ReadFromResource(timeOut As Integer)
   Try
      rwl.AcquireReaderLock(timeOut)
      Try
         ' It's safe for this thread to read from the shared resource.
         Display("reads resource value " & resource)
         Interlocked.Increment(reads)
      Finally
         ' Ensure that the lock is released.
         rwl.ReleaseReaderLock()
      End Try
   Catch ex As ApplicationException
      ' The reader lock request timed out.
      Interlocked.Increment(readerTimeouts)
   End Try
End Sub

};

}

End Module

Hinweise

ReleaseReaderLock Dekrementiert die Sperranzahl. Wenn die Anzahl null erreicht, wird die Sperre freigegeben.

Hinweis

Wenn ein Thread über die Writer-Sperre verfügt, hat der Aufruf ReleaseReaderLock denselben Effekt wie das Aufrufen ReleaseWriterLock. Wenn ein Thread keine Sperrungen aufweist, löst der Aufruf ReleaseReaderLock eine ApplicationException.

Gilt für

Siehe auch