Title: Getting printer information
Question: I want to get details of the printer's paper and margins, but GetDeviceCaps does not work reliably if I am not already printing.
Answer:
From Steve Schafer:
PaperWidth := GetDeviceCaps(Printer.Canvas.Handle, PHYSICALWIDTH);
PaperHeight := GetDeviceCaps(Printer.Canvas.Handle, PHYSICALHEIGHT);
PrintableWidth := GetDeviceCaps(Printer.Canvas.Handle, HORZRES);
PrintableHeight := GetDeviceCaps(Printer.Canvas.Handle, VERTRES);
LeftMargin := GetDeviceCaps(Printer.Canvas.Handle, PHYSICALOFFSETX);
TopMargin := GetDeviceCaps(Printer.Canvas.Handle, PHYSICALOFFSETY);
RightMargin := PaperWidth - PrintableWidth - LeftMargin;
BottomMargin := PaperHeight - PrintableHeight - TopMargin;
You can't access Printer.Canvas.Handle without initiating a print job;
you can instead use CreateIC to get a handle to an information context
that you can pass to GetDeviceCaps:
var
Device, Driver, Port: array[0..80] of Char;
DevMode: THandle;
IC: THandle;
begin
Printer.GetPrinter(Device, Driver, Port, DevMode);
Printer.SetPrinter(Device, Driver, Port, 0);
Printer.GetPrinter(Device, Driver, Port, DevMode);
IC := CreateIC(Driver, Device, Port, nil);
...
PaperWidth := GetDeviceCaps(IC, PHYSICALWIDTH);
...
DeleteDC(IC);
end;