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AutomationPeer.ListenerExists(AutomationEvents) Method

  • Reference

Definition

Namespace:
System.Windows.Automation.Peers
Assembly:
PresentationCore.dll

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

public:
 static bool ListenerExists(System::Windows::Automation::Peers::AutomationEvents eventId);
public static bool ListenerExists (System.Windows.Automation.Peers.AutomationEvents eventId);
static member ListenerExists : System.Windows.Automation.Peers.AutomationEvents -> bool
Public Shared Function ListenerExists (eventId As AutomationEvents) As Boolean

Parameters

eventId
AutomationEvents

One of the enumeration values.

Returns

Boolean

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

Remarks

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.

Note

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.

Applies to

See also