Dispatcher.DisableProcessing Method

Definition

Namespace:

System.Windows.Threading

Assembly:

WindowsBase.dll

Disables processing of the Dispatcher queue.

public:
 System::Windows::Threading::DispatcherProcessingDisabled DisableProcessing();

public System.Windows.Threading.DispatcherProcessingDisabled DisableProcessing ();

member this.DisableProcessing : unit -> System.Windows.Threading.DispatcherProcessingDisabled

Public Function DisableProcessing () As DispatcherProcessingDisabled

Returns

DispatcherProcessingDisabled

A structure used to re-enable dispatcher processing.

Examples

The following example shows how to disable dispatcher processing and re-enable dispatcher processing. DisableProcessing is called in a using statement. DisableProcessing returns a DispatcherProcessingDisabled structure that is used as the object to be disposed when the using block finishes. When Dispose is called on the DispatcherProcessingDisabled structure, dispatcher processing is re-enabled.

// The Dispose() method is called at the end of the using statement.
// Calling Dispose on the DispatcherProcessingDisabled structure, 
// which is returned from the call to DisableProcessing, will
// re-enalbe Dispatcher processing.
using (Dispatcher.DisableProcessing())
{
    // Do work while the dispatcher processing is disabled.
    Thread.Sleep(2000);
}

' The Dispose() method is called at the end of the using statement.
' Calling Dispose on the DispatcherProcessingDisabled structure, 
' which is returned from the call to DisableProcessing, will
' re-enable Dispatcher processing.
Using Dispatcher.DisableProcessing()
    ' Do work while the dispatcher processing is disabled.
    Thread.Sleep(2000)
End Using

Remarks

Disabling dispatcher processing is an advanced method that is intended to eliminate the chance of unrelated reentrancy.

The effects of disabling processing are as follows:

• CLR locks will not pump messages internally.

• DispatcherFrame objects are not allowed to be pushed.

• Message processing is not permitted.

The DispatcherProcessingDisabled structure that DisableProcessing returns when it is called can be used to re-enable dispatcher processing. Calling Dispose on the DispatcherProcessingDisabled structure re-enables processing.

DisableProcessing can only be called on the thread the Dispatcher is associated with.