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Responding to System Events Sample

This sample uses the SystemEvents class, which allows an application to react to events raised by system activity.

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Security noteSecurity Note:

This sample code is intended to illustrate a concept, and it shows only the code that is relevant to that concept. It may not meet the security requirements for a specific environment, and it should not be used exactly as shown. We recommend that you add security and error-handling code to make your projects more secure and robust. Microsoft provides this sample code "AS IS" with no warranties.

To run this sample

  • Press F5.

The Microsoft.Win32.SystemEvents class provides a number of public events that you can sink in your code. This sample demonstrates five of the available events of the SystemEvents class. Select the check box on the form to add an event handler for the event. The events and how to trigger them are shown in the following table.



How to trigger



Change the screen resolution.



Modify the current system time.

Power mode


If running on a laptop, change the plugged-in status.

User preference


Change any Windows setting. For example, right-click the desktop to display the Display Properties dialog box and change a setting.

Installed fonts


Install or delete a font.