Programmatically changing the “presentation display mode”

Question

The presentation display modes are those you see when using the Windows+p shortcut:

1. Computer Only
2. Duplicate

Answer 1

You can obtain and change the display setting using EnumDisplaySettingsEx and ChangeDisplaySettingsEx:

The ChangeDisplaySettingsEx function changes the settings of the specified display device to the specified graphics mode.

Check this Codeproject project and this Stackoverflow question for example code