GetDeviceCaps function

In unit LCLIntf

Returns various device specific information.

Declaration

pascal

function GetDeviceCaps(DC: HDC; Index: Integer): Integer

Description

Returns information about any DC (Device Context), which might be the screen DC representing the monitor, a control canvas or a off-screen bitmap canvas. The following constants can be utilized in the index argument:

HORZSIZE
VERTSIZE
HORZRES
BITSPIXEL
PLANES
SIZEPALETTE
LOGPIXELSX - the DPI in the X axis
LOGPIXELSY - the DPI in the Y axis
VERTRES
NUMRESERVED

An example showing how to obtain the screen DPI for the X axis using GetDeviceCaps, which is the method utilized by TScreen.PixelsPerInch:

var
  DC: HDC;
begin
  DC := GetDC(0);
  FDPI := GetDeviceCaps(DC,LOGPIXELSX); // DPI in pixels per inch
  ReleaseDC(0, DC);
end;

GetDeviceCaps function

Declaration

Description

See also