แก้ไข

แชร์ผ่าน


CanExecuteRoutedEventArgs.Command Property

Definition

Gets the command associated with this event.

public:
 property System::Windows::Input::ICommand ^ Command { System::Windows::Input::ICommand ^ get(); };
public System.Windows.Input.ICommand Command { get; }
member this.Command : System.Windows.Input.ICommand
Public ReadOnly Property Command As ICommand

Property Value

The command. Unless the command is a custom command, this is generally a RoutedCommand. There is no default value.

Examples

The following example creates a CanExecuteRoutedEventHandler which handles multiple commands. If the Command property is equal to the Play command and the method IsPlaying returns false, CanExecute is set to true; otherwise, CanExecute is set to false. If the Command property is equal to the Stop command and the method IsPlaying returns true, CanExecute is set to true; otherwise, CanExecute is set to false.

private void CanExecuteDisplayCommand(object sender,
    CanExecuteRoutedEventArgs e)
{
    RoutedCommand command = e.Command as RoutedCommand;

    if (command != null)
    {
        if (command == MediaCommands.Play)
        {
            if (IsPlaying() == false)
            {
                e.CanExecute = true;
            }
            else
            {
                e.CanExecute = false;
            }
        }

        if (command == MediaCommands.Stop)
        {
            if (IsPlaying() == true)
            {
                e.CanExecute = true;
            }
            else
            {
                e.CanExecute = false;
            }
        }
    }
}
Private Sub CanExecuteDisplayCommand(ByVal sender As Object, ByVal e As CanExecuteRoutedEventArgs)
    Dim command As RoutedCommand = TryCast(e.Command, RoutedCommand)

    If command IsNot Nothing Then
        If command Is MediaCommands.Play Then
            If IsPlaying() = False Then
                e.CanExecute = True
            Else
                e.CanExecute = False
            End If
        End If

        If command Is MediaCommands.Stop Then
            If IsPlaying() = True Then
                e.CanExecute = True
            Else
                e.CanExecute = False
            End If
        End If
    End If
End Sub

Remarks

For more information on commanding, see the Commanding Overview.

Applies to

See also