AutomationPeer.ListenerExists(AutomationEvents) Method

Reference

Definition

Namespace:: System.Windows.Automation.Peers

Assembly:: PresentationCore.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

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

Dela via