How to: Determine number of colours

[Killer42]

This simple function may be called to determine the colour "depth" of the display, using the GetDeviceCaps API.

Private Declare Function GetDeviceCaps Lib "GDI32" (ByVal hDC As Long, ByVal nIndex As Long) As Long
 
Function DeviceColors(hDC As Long) As Single
  Const PLANES = 14
  Const BITSPIXEL = 12
  DeviceColors = 2 ^ (GetDeviceCaps(hDC, PLANES) * GetDeviceCaps(hDC, BITSPIXEL))
End Function
 

To use this function, just pass it the hDC of your current form.
Some typical values returned...
4,294,967,296 = "True Color" (32 bit)
65,536 = "High Color" (16 bit)