Occurs when the user is trying to log off or shut down the system.
Assembly: System (in System.dll)
This is a cancelable event. Setting the Cancel property to true will request that the session continues to run. It provides no guarantee that the session will not end.
If you are using Closing event will fire before this event.in a Windows form to detect a system logoff or reboot, there is no deterministic way to decide whether the
If you want to perform some special tasks before Closing is fired, you need to ensure that fires before Closing. To do this, you need to trap the WM_QUERYENDSESSION in the form by overriding the WndProc function. This example demonstrates how to do this.
Console applications do not raise theevent.
This event is only raised if the message pump is running. In a Windows service, unless a hidden form is used or the message pump has been started manually, this event will not be raised. For a code example that shows how to handle system events by using a hidden form in a Windows service, see the SystemEvents class.
Because this is a static event, you must detach your event handlers when your application is disposed, or memory leaks will result.
Available since 1.1