如何得知系統使用的字型是 large 還是 small?

try this:

function SmallFonts: boolean;
{returns TRUE if  small fonts are set, FALSE if using Large Fonts }
var
  DC : HDC; { used to check for number of colors available }
begin
  DC := GetDC(0);
  Result :=   (GetDeviceCaps(DC, LOGPIXELSX) = 96); 
  { LOGPIXELSX will = 120 if large fonts are in use }
  ReleaseDC(0, DC);
end;

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