ListenerExists Method
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AutomationPeer.ListenerExists Method (AutomationEvents)


Gets a value that indicates whether UI Automation is listening for the specified event. 

Namespace:   System.Windows.Automation.Peers
Assembly:  PresentationCore (in PresentationCore.dll)

public static bool ListenerExists(
	AutomationEvents eventId


Type: System.Windows.Automation.Peers.AutomationEvents

One of the enumeration values.

Return Value

Type: System.Boolean

A boolean that indicates whether UI Automation is listening for the event.

Typically, you call this method before creating the AutomationPeer that raises the event. This method is a performance measure because if UI Automation does not listen for the event, it does not make sense to create a peer to raise one.


This method is static and only answers if a delegate listens for the specified event in UI Automation, not for an event on a specific element. UI Automation can create broadcast listeners; therefore the per-element information is irrelevant.

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