DispatcherHooks.OperationStarted Event   
Definition
Important
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Occurs when an operation is invoked.
public:
 event System::Windows::Threading::DispatcherHookEventHandler ^ OperationStarted;
	[add: System.Security.SecurityCritical]
[remove: System.Security.SecurityCritical]
public event System.Windows.Threading.DispatcherHookEventHandler OperationStarted;
	public event System.Windows.Threading.DispatcherHookEventHandler OperationStarted;
	[<add: System.Security.SecurityCritical>]
[<remove: System.Security.SecurityCritical>]
member this.OperationStarted : System.Windows.Threading.DispatcherHookEventHandler 
	member this.OperationStarted : System.Windows.Threading.DispatcherHookEventHandler 
	Public Custom Event OperationStarted As DispatcherHookEventHandler 
	Event Type
- Attributes
 
Remarks
Typically, this event is due to the BeginInvoke API, but the Invoke API can also cause this event if any priority other than DispatcherPriority.Send is specified, or if the destination dispatcher is owned by a different thread.
Any thread can post operations, so this event can be raised by any thread.