How to check if the current printer is ready to print in color

Problem/Question/Abstract:

How can I find out whether the current printer is ready to print in colour, rather than just capable of printing in colour?

Answer:

Solve 1:

This works for some but not all printers, depending on the driver capabilities:

{ ... }
var
  Dev, Drv, Prt: array[0..255] of Char;
  DM1: PDeviceMode;
  DM2: PDeviceMode;
  Sz: Integer;
  DevM: THandle;
begin
  Printer.PrinterIndex := -1;
  Printer.GetPrinter(Dev, Drv, Prt, DevM);
  DM1 := nil;
  DM2 := nil;
  Sz := DocumentProperties(0, 0, Dev, DM1^, DM2^, 0);
  GetMem(DM1, Sz);
  DocumentProperties(0, 0, Dev, DM1^, DM2^, DM_OUT_BUFFER);
  if DM1^.dmColor > 1 then
    Label1.Caption := Dev + ': Color'
  else
    Label1.Caption := Dev + ': Black and White';
  if DM1^.dmFields and DM_Color <> 0 then
    Label2.Caption := 'Printer supports color printing'
  else
    Label2.Caption := 'Printer does not support color printing';
  FreeMem(DM1);
end;


Solve 2:

function IsColorPrinter: bool;
var
  Device: array[0..MAX_PATH] of char;
  Driver: array[0..MAX_PATH] of char;
  Port: array[0..MAX_PATH] of char;
  hDMode: THandle;
  PDMode: PDEVMODE;
begin
  result := False;
  Printer.PrinterIndex := Printer.PrinterIndex;
  Printer.GetPrinter(Device, Driver, Port, hDMode);
  if hDMode <> 0 then
  begin
    pDMode := GlobalLock(hDMode);
    if pDMode <> nil then
    begin
      if ((pDMode^.dmFields and dm_Color) = dm_Color) then
      begin
        result := True;
      end;
      GlobalUnlock(hDMode);
    end;
  end;
end;

function SetPrinterColorMode(InColor: bool): bool;
var
  Device: array[0..MAX_PATH] of char;
  Driver: array[0..MAX_PATH] of char;
  Port: array[0..MAX_PATH] of char;
  hDMode: THandle;
  PDMode: PDEVMODE;
begin
  result := False;
  Printer.PrinterIndex := Printer.PrinterIndex;
  Printer.GetPrinter(Device, Driver, Port, hDMode);
  if hDMode <> 0 then
  begin
    pDMode := GlobalLock(hDMode);
    if pDMode <> nil then
    begin
      if (pDMode^.dmFields and dm_Color) = dm_Color then
      begin
        if (InColor) then
        begin
          pDMode^.dmColor := DMCOLOR_COLOR;
        end
        else
        begin
          pDMode^.dmColor := DMCOLOR_MONOCHROME;
        end;
        result := True;
      end;
      GlobalUnlock(hDMode);
      Printer.PrinterIndex := Printer.PrinterIndex;
    end;
  end;
end;