AutomationPropertyChangedEventArgs(AutomationProperty, Object, Object) Konstruktor

Definice

Obor názvů:

System.Windows.Automation

Sestavení:

UIAutomationTypes.dll

Inicializuje novou instanci AutomationPropertyChangedEventArgs třídy.

public:
 AutomationPropertyChangedEventArgs(System::Windows::Automation::AutomationProperty ^ property, System::Object ^ oldValue, System::Object ^ newValue);

public AutomationPropertyChangedEventArgs (System.Windows.Automation.AutomationProperty property, object oldValue, object newValue);

new System.Windows.Automation.AutomationPropertyChangedEventArgs : System.Windows.Automation.AutomationProperty * obj * obj -> System.Windows.Automation.AutomationPropertyChangedEventArgs

Public Sub New (property As AutomationProperty, oldValue As Object, newValue As Object)

Parametry

property

AutomationProperty

Identifikátor vlastnosti, která se změnila.

oldValue

Object

Předchozí hodnota vlastnosti.

newValue

Object

Nová hodnota vlastnosti.

Příklady

Následující příklad vytvoří a vyvolá událost při změně vlastnosti.

/// <summary>
/// Raises an event when the IsEnabled property on a control is changed.
/// </summary>
/// <param name="provider">The UI Automation provider for the control.</param>
/// <param name="newValue">The current enabled state.</param>
private void RaiseEnabledEvent(IRawElementProviderSimple provider, bool newValue)
{
    if (AutomationInteropProvider.ClientsAreListening)
    {
        AutomationPropertyChangedEventArgs args =
            new AutomationPropertyChangedEventArgs(AutomationElement.IsEnabledProperty,
                !newValue, newValue);
        AutomationInteropProvider.RaiseAutomationPropertyChangedEvent(provider, args);
    }
}

''' <summary>
''' Raises an event when the IsEnabled property on a control is changed.
''' </summary>
''' <param name="provider">The UI Automation provider for the control.</param>
''' <param name="newValue">The current enabled state.</param>
Private Sub RaiseEnabledEvent(ByVal provider As IRawElementProviderSimple, ByVal newValue As Boolean) 
    If AutomationInteropProvider.ClientsAreListening Then
        Dim args As New AutomationPropertyChangedEventArgs(AutomationElement.IsEnabledProperty, Not newValue, newValue)
        AutomationInteropProvider.RaiseAutomationPropertyChangedEvent(provider, args)
    End If

End Sub

Poznámky

oldValuemůže být null (Nothing v Visual Basic) pokud předchozí hodnota není snadno dostupná.