API Delphi

Question:
How can I determine in code if a canvas is a Metafile Canvas?
Answer:
You can check the return value of the Windows API function
GetDeviceCaps() to check if a given dc is used by a Metafile.
Example:
if (GetDeviceCaps(Canvas.Handle, TECHNOLOGY) and
DT_METAFILE) = DT_METAFILE then
IsMetafileDc := True;