ReaderWriterLockSlim.ExitReadLock Method ()

 

Reduces the recursion count for read mode, and exits read mode if the resulting count is 0 (zero).

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

Public Sub ExitReadLock

Exception Condition
SynchronizationLockException

The current thread has not entered the lock in read mode.

This method is not sensitive to recursion order. For example, if a thread enters a lock in upgradeable mode and then enters the lock in read mode, the order in which the thread exits the two modes does not matter. If a lock allows recursion, a thread can enter the lock in write mode and then enter it recursively in read mode; the order in which the thread exits read mode and write mode does not matter.

Exiting the lock might signal other waiting threads.

The following example shows how to use a finally block to execute the ExitReadLock method, ensuring that the caller exits read mode. The method shown in the example retrieves the value associated with a key. If the key is not found, the exception thrown by the inner Dictionary(Of TKey, TValue) is allowed to terminate the method. The EnterReadLock method is used to enter read mode.

This code is part of a larger example provided for the ReaderWriterLockSlim class.

Private cacheLock As New ReaderWriterLockSlim()
Private innerCache As New Dictionary(Of Integer, String)
Public Function Read(ByVal key As Integer) As String
    cacheLock.EnterReadLock()
    Try
        Return innerCache(key)
    Finally
        cacheLock.ExitReadLock()
    End Try
End Function

Universal Windows Platform
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
Return to top
Show: