从App.xaml.cs关闭WPF应用程序

using System.Windows;

namespace WpfApp
{
    public partial class App : Application
    {
        public void CloseApplication()
        {
            Application.Current.Shutdown();
        }
    }
}

using System.Windows;

namespace WpfApp
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            Closed += (sender, args) => App.Current.Shutdown();
        }
    }
}