<Window x:Class="ApplicationShutdownSample.ChildWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Application Shutdown Sample" Closing="ChildWindow_Closing" Closed="ChildWindow_Closed"> <Grid> </Grid> </Window> //File:Window.xaml.cs using System; using System.ComponentModel; using System.Windows; namespace ApplicationShutdownSample { public partial class ChildWindow : Window { public ChildWindow() { InitializeComponent(); } void ChildWindow_Closing(object sender, CancelEventArgs e) { Console.WriteLine("Closing"); MessageBoxResult result = MessageBox.Show("Allow Shutdown?", "Application Shutdown Sample", MessageBoxButton.YesNo, MessageBoxImage.Question); e.Cancel = (result == MessageBoxResult.No); } void ChildWindow_Closed(object sender, EventArgs e) { Console.WriteLine("Closed"); } } }