ReaderWriterLock.ReleaseReaderLock-Methode

Verringert die Sperrenanzahl.

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

Syntax

'Declaration
Public Sub ReleaseReaderLock
'Usage
Dim instance As ReaderWriterLock

instance.ReleaseReaderLock

public void ReleaseReaderLock ()

public:
void ReleaseReaderLock ()

public void ReleaseReaderLock ()

public function ReleaseReaderLock ()

Ausnahmen

Ausnahmetyp	Bedingung
ApplicationException	Der Thread verfügt weder über Lese- noch über Schreibsperren.

Hinweise

ReleaseReaderLock verringert die Sperrenanzahl. Wenn die Anzahl 0 (null) erreicht, wird die Sperre aufgehoben.

Hinweis

Wenn der Thread über eine Schreibsperre verfügt, entspricht das Aufrufen von ReleaseReaderLock dem Aufrufen von ReleaseWriterLock. Wenn der Thread keine Sperren enthält, löst ReleaseReaderLock eine ApplicationException aus.

Beispiel

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

Public Class Test
    ' Declaring the ReaderWriterLock at the class level
    ' makes it visible to all threads.
    Private Shared rwl As New ReaderWriterLock()
    ' For this example, the shared resource protected by the
    ' ReaderWriterLock is just an integer.
    Private Shared resource As Integer = 0

...
    ' Shows how to request and release a reader lock, and
    ' how to handle time-outs.
    Shared Sub ReadFromResource(timeOut As Integer)
        Try
            rwl.AcquireReaderLock(timeOut)
            Try
                ' It is 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 'ReadFromResource

...
End Class 'Test 

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

public class Test
{
    // Declaring the ReaderWriterLock at the class level
    // makes it visible to all threads.
    static ReaderWriterLock rwl = new ReaderWriterLock();
    // For this example, the shared resource protected by the
    // ReaderWriterLock is just an integer.
    static int resource = 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("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);
        }
    }

...
}

// 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;


...
   // 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 );
      }

   }



...
};

// The complete code is located in the ReaderWriterLock
// class topic.
import System.*;
import System.Threading.*;
import System.Threading.Thread;    

public class Test
{
    // Declaring the ReaderWriterLock at the class level
    // makes it visible to all threads.
    private static ReaderWriterLock rwl = new ReaderWriterLock();

    // For this example, the shared resource protected by the
    // ReaderWriterLock is just an integer.
    private static int resource = 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(("reads resource value " + resource));
                Interlocked.Increment(reads);
            }
            finally {
                // Ensure that the lock is released.
                rwl.ReleaseReaderLock();
            }
        }
        catch (ApplicationException exp) {
            // The reader lock request timed out.
            Interlocked.Increment(readerTimeouts);
        }
    } //ReadFromResource

...
}

Plattformen

Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

Siehe auch

Referenz

ReaderWriterLock-Klasse
ReaderWriterLock-Member
System.Threading-Namespace

Weitere Ressourcen

Verwaltetes Threading
Lese-/Schreibsperren