AutomationPeer.ListenerExists(AutomationEvents) Method
Definition
Important
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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
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.