WPF MVVM:如何关闭窗口

public class CloseWindowCommand : ICommand
{
    public event EventHandler CanExecuteChanged;

    public bool CanExecute(object parameter)
    {
        return true; // 可以根据需要进行逻辑判断，决定是否可以执行命令
    }

    public void Execute(object parameter)
    {
        Window window = parameter as Window;
        if (window != null)
        {
            window.Close();
        }
    }
}

public class MainViewModel : INotifyPropertyChanged
{
    public ICommand CloseWindowCommand { get; private set; }

    public MainViewModel()
    {
        CloseWindowCommand = new CloseWindowCommand();
    }

    // 其他ViewModel的代码...
}

<Window x:Class="MyApp.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:MyApp"
        Title="MyApp" Height="450" Width="800">
    <Window.DataContext>
        <local:MainViewModel />
    </Window.DataContext>
    
    <Grid>
        <!-- 窗口内容 -->
    </Grid>
    
    <Button Content="Close" Command="{Binding CloseWindowCommand}" />
</Window>