再学 GDI+[2]: DrawLine - 绘制直线

本例效果图:

---

unit Unit1;



interface



uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs;



type

  TForm1 = class(TForm)

    procedure FormPaint(Sender: TObject);

  end;



var

  Form1: TForm1;



implementation



{$R *.dfm}



uses GDIPOBJ, GDIPAPI;



procedure TForm1.FormPaint(Sender: TObject);

var

  g: TGPGraphics;

  p: TGPPen;

begin

  g := TGPGraphics.Create(Canvas.Handle);

  p := TGPPen.Create(MakeColor(255,0,0), 2);

  g.Clear(MakeColor(255,255,255));



  g.DrawLine(p, 20, 40, 200, 40);                                 {参数是整数}

  g.DrawLine(p, MakePoint(20,60), MakePoint(200,60));             {参数是点(整数)}

  g.DrawLine(p, 20.9, 80.0, 200.9, 80.0);                         {参数是小数}

  g.DrawLine(p, MakePoint(20.9, 100.0), MakePoint(200.9, 100.0)); {参数是点(小数)}



  g.Free;

  p.Free;

end;



end.