WPF MVVM: How to close a window

Question

I have a Button that closes my window when it\'s clicked:

Ok

Answer 1

I'd personally use a behaviour to do this sort of thing:

public class WindowCloseBehaviour : Behavior
{
    public static readonly DependencyProperty CommandProperty =
      DependencyProperty.Register(
        "Command",
        typeof(ICommand),
        typeof(WindowCloseBehaviour));

    public static readonly DependencyProperty CommandParameterProperty =
      DependencyProperty.Register(
        "CommandParameter",
        typeof(object),
        typeof(WindowCloseBehaviour));

    public static readonly DependencyProperty CloseButtonProperty =
      DependencyProperty.Register(
        "CloseButton",
        typeof(Button),
        typeof(WindowCloseBehaviour),
        new FrameworkPropertyMetadata(null, OnButtonChanged));

    public ICommand Command
    {
        get { return (ICommand)GetValue(CommandProperty); }
        set { SetValue(CommandProperty, value); }
    }

    public object CommandParameter
    {
        get { return GetValue(CommandParameterProperty); }
        set { SetValue(CommandParameterProperty, value); }
    }

    public Button CloseButton
    {
        get { return (Button)GetValue(CloseButtonProperty); }
        set { SetValue(CloseButtonProperty, value); }
    }

    private static void OnButtonChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        var window = (Window)((WindowCloseBehaviour)d).AssociatedObject;
        ((Button) e.NewValue).Click +=
            (s, e1) =>
            {
                var command = ((WindowCloseBehaviour)d).Command;
                var commandParameter = ((WindowCloseBehaviour)d).CommandParameter;
                if (command != null)
                {
                    command.Execute(commandParameter);                                                      
                }
                window.Close();
            };
        }
    }

You can then attach this to your Window and Button to do the work:

    
        
    
    
        Close
    

I've added Command and CommandParameter here so you can run a command before the Window closes.