ReaderWriterLockSlim.ExitReadLock Method
Definition
Important
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Reduces the recursion count for read mode, and exits read mode if the resulting count is 0 (zero).
public:
void ExitReadLock();public void ExitReadLock ();member this.ExitReadLock : unit -> unitPublic Sub ExitReadLock ()Exceptions
The current thread has not entered the lock in read mode.
Examples
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<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 ReaderWriterLockSlim cacheLock = new ReaderWriterLockSlim();
private Dictionary<int, string> innerCache = new Dictionary<int, string>();
Private cacheLock As New ReaderWriterLockSlim()
Private innerCache As New Dictionary(Of Integer, String)
public string Read(int key)
{
cacheLock.EnterReadLock();
try
{
return innerCache[key];
}
finally
{
cacheLock.ExitReadLock();
}
}
Public Function Read(ByVal key As Integer) As String
cacheLock.EnterReadLock()
Try
Return innerCache(key)
Finally
cacheLock.ExitReadLock()
End Try
End Function
Remarks
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.
