Exclude your Xojo window from screenshots on Windows

Did you know that Windows provides APIs for developers to exclude their windows from being screenshoted?

We only need to set the display affinity:

Window1.WindowDisplayAffinityMBS = &h11

Checkout the details on the WindowDisplayAffinityMBS property. We can set it to 0 for no restriction, which is the default. Value 1 makes the window only draw itself when shown on monitor. So printing the window may not work. And &h11 = 17 makes it disappear from screen captures.

This was of course invented in Windows 7 for DRM protection. To make it impossible to take a screenshot from playing a DVD or other videos with DRM. There are still tools to capture screen at display driver level or people simply film the display with their camera.

Please try and see if have use for this. The biggest plugin in space...