Dispatcher.CheckAccess Method ()

 
System_CAPS_noteNote

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Determines whether the calling thread is the thread associated with this Dispatcher.

Namespace:   System.Windows.Threading
Assembly:  WindowsBase (in WindowsBase.dll)

member CheckAccess : unit -> bool

Return Value

Type: System.Boolean

true if the calling thread is the thread associated with this Dispatcher; otherwise, false.

Only the Dispatcher that a DispatcherObject is created on may access the object. Use Invoke or BeginInvoke to access the object from a different thread.

CheckAccess can be called from any thread.

The difference between CheckAccess and VerifyAccess is CheckAccess returns a Boolean indicating whether the calling thread has access to the Dispatcher and VerifyAccess throws an exception.

The following example uses CheckAccess to determine whether a thread has access to a Button. The CheckAccess method on the Dispatcher associated with the Button is called to verify access to the thread. If the calling thread has access to the Dispatcher, the Button is updated by accessing the members of the Button; otherwise, a delegate, which accepts a Button as an argument, is placed onto the Dispatcher. The Dispatcher will delegate the work of updating the Button.

No code example is currently available or this language may not be supported.

.NET Framework
Available since 3.0
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
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