CommandManager.AddExecutedHandler Método

Definição

Espaço de Nomes:

System.Windows.Input

Assemblagem:

PresentationCore.dll

Anexa o especificado ExecutedRoutedEventHandler ao elemento especificado.

public:
 static void AddExecutedHandler(System::Windows::UIElement ^ element, System::Windows::Input::ExecutedRoutedEventHandler ^ handler);

public static void AddExecutedHandler(System.Windows.UIElement element, System.Windows.Input.ExecutedRoutedEventHandler handler);

static member AddExecutedHandler : System.Windows.UIElement * System.Windows.Input.ExecutedRoutedEventHandler -> unit

Public Shared Sub AddExecutedHandler (element As UIElement, handler As ExecutedRoutedEventHandler)

Parâmetros

element

UIElement

O elemento a que se deve prender handler .

handler

ExecutedRoutedEventHandler

O manipulador executado.

Exceções

ArgumentNullException

element ou handler é null.

Exemplos

O exemplo seguinte cria um CanExecuteRoutedEventHandler e um ExecutedRoutedEventHandler e associa-os a Button um que é uma fonte de comando para o Help comando.

Primeiro, o Button é criado e associado ao Help comando.

<Button Command="ApplicationCommands.Help"
        Name="helpButton">Help</Button>

De seguida, os CanExecuteRoutedEventHandler e ExecutedRoutedEventHandler os são criados.

private void HelpCmdExecuted(object sender, ExecutedRoutedEventArgs e)
{
    // OpenHelpFile opens the help file
    OpenHelpFile();
}

Private Sub HelpCmdExecuted(ByVal sender As Object, ByVal e As ExecutedRoutedEventArgs)
    ' OpenHelpFile opens the help file
    OpenHelpFile()
End Sub

private void HelpCmdCanExecute(object sender, CanExecuteRoutedEventArgs e)
{
    // HelpFilesExists() determines if the help file exists
    if (HelpFileExists())
    {
        e.CanExecute = true;
    }
    else
    {
        e.CanExecute = false;
    }
}

Private Sub HelpCmdCanExecute(ByVal sender As Object, ByVal e As CanExecuteRoutedEventArgs)
    ' HelpFilesExists() determines if the help file exists
    If HelpFileExists() = True Then
        e.CanExecute = True
    Else
        e.CanExecute = False
    End If
End Sub

E finalmente, os manipuladores são ligados ao Button usando e AddCanExecuteHandlerAddExecutedHandler.

CommandManager.AddExecutedHandler(helpButton, HelpCmdExecuted);
CommandManager.AddCanExecuteHandler(helpButton, HelpCmdCanExecute);

CommandManager.AddExecutedHandler(helpButton, AddressOf HelpCmdExecuted)
CommandManager.AddCanExecuteHandler(helpButton, AddressOf HelpCmdCanExecute)

Ver também

• RoutedCommand
• ICommand