ReaderWriterLock.ReleaseReaderLock 方法

定義

命名空間:

System.Threading

組件:

netstandard.dll, System.Threading.dll

來源:

ReaderWriterLock.cs

減量鎖定計數。

public:
 void ReleaseReaderLock();

public void ReleaseReaderLock();

member this.ReleaseReaderLock : unit -> unit

Public Sub ReleaseReaderLock ()

例外狀況

ApplicationException

執行緒沒有任何讀取或寫入鎖定。

範例

以下程式碼範例說明如何取得並釋放讀取鎖，以及如何處理請求逾時拋出的例外。

此程式碼是該類別更大 ReaderWriterLock 範例的一部分。

// 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

// 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

備註

ReleaseReaderLock 減少鎖數。 當計數歸零時，鎖會被解除。

備註

若執行緒有寫入鎖定，呼叫 ReleaseReaderLock 與呼叫 ReleaseWriterLock的效果相同。 如果執行緒沒有鎖，呼叫 ReleaseReaderLock 會拋出一個 ApplicationException。

另請參閱

• 管理的執行緒