Occurs when an application is started.
Assembly: System.Windows (in System.Windows.dll)
XMLNS for XAML: Not mapped to an xmlns.
The Startup event should not be used by Windows Phone applications. Instead, use the application lifetime events exposed by the PhoneApplicationService class. When an application is being launched for the first time the Launching event is raised. When an application is being reactivated after previously being suspended, the Activated event is raised. For more information on the lifecycle of Windows Phone applications, see Activation and deactivation best practices for Windows Phone 8.