Delphi 全局画点TCanvas.Pixels[X,Y]

procedure TForm1.btnChangePixelClick(Sender: TObject);

var

    baseX : integer ;

    baseY : integer ;

    i,j : integer;

    c : TCanvas;

begin

    baseX :=100;

    baseY := 100;

    c := TCanvas.create;

    try

        c.Handle := GetDC(0);

        for i := baseX - 1 to baseX + 1 do

        begin

            for j := baseY - 1 to baseY + 1 do

            begin

                c.Pixels[i,j] := RGB($FF,0,0);

                //self.Canvas.Pixels[i,j] := RGB($FF,0,0);

            end;

        end;

    finally

      c.Free;

    end;

end;

end.