<Application xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Class="ActivationSample.App" StartupUri="MainWindow.xaml" Startup="App_Startup" Activated="App_Activated" Deactivated="App_Deactivated" Exit="App_Exit"> </Application> //File:Window.xaml.cs using System; using System.Windows; using System.Windows.Forms; using System.Windows.Threading; namespace ActivationSample { public partial class App : System.Windows.Application { void App_Startup(object sender, StartupEventArgs e) { } void App_Activated(object sender, EventArgs e) { Console.WriteLine("App_Activated"); } void App_Deactivated(object sender, EventArgs e) { Console.WriteLine("Deactivated"); } void App_Exit(object sender, ExitEventArgs e) { Console.WriteLine("Exit"); } } }