Releases the lock, regardless of the number of times the thread acquired the lock.
Assembly: mscorlib (in mscorlib.dll)
The following code example shows how to use the method to release the lock, regardless of how many times it has been acquired by the thread, and how to restore the state of the lock later.
This code is part of a larger example provided for the ReaderWriterLock class.
' 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 release all locks and later restore ' the lock state. Shows how to use sequence numbers ' to determine whether another thread has obtained ' a writer lock since this thread last accessed the ' resource. Shared Sub ReleaseRestore(timeOut As Integer) Dim lastWriter As Integer Try rwl.AcquireReaderLock(timeOut) Try ' It is safe for this thread to read from ' the shared resource. Cache the value. (You ' might do this if reading the resource is ' an expensive operation.) Dim resourceValue As Integer = resource Display("reads resource value " & resourceValue) Interlocked.Increment(reads) ' Save the current writer sequence number. lastWriter = rwl.WriterSeqNum ' Release the lock, and save a cookie so the ' lock can be restored later. Dim lc As LockCookie = rwl.ReleaseLock() ' Wait for a random interval (up to a ' quarter of a second), and then restore ' the previous state of the lock. Note that ' there is no time-out on the Restore method. Thread.Sleep(rnd.Next(250)) rwl.RestoreLock(lc) ' Check whether other threads obtained the ' writer lock in the interval. If not, then ' the cached value of the resource is still ' valid. If rwl.AnyWritersSince(lastWriter) Then resourceValue = resource Interlocked.Increment(reads) Display("resource has changed " & resourceValue) Else Display("resource has not changed " & resourceValue) End If 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 'ReleaseRestore ... End Class 'Test
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.