Is there a way to determine the physical size of the monitor?

Question

In inches, e.g. 21' monitor. The app is a standard WinForms app.

EDIT: It appears there really isn't a reliable way to accomplish what I need.

Answer 1

This cannot be guaranteed. Windows cannot know the size of the monitor unless its driver interrogates it and reports the reply to windows.

However, you might want to try

SystemInformation.PrimaryMonitorSize

or GetDeviceCaps(dc, HORZSIZE) and GetDeviceCaps(dc, VERTSIZE) and then calulate the square on the hypotenuse.

Note that there is also an accepted answer to identical question right here on Stack Overflow.