再学 GDI+[2]: DrawLine - 绘制直线

 

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs;

type
  TForm1 = class(TForm)
    procedure FormPaint(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}
uses
  GDIPAPI,GDIPOBJ;
procedure TForm1.FormPaint(Sender: TObject);
var
  g:TGPGraphics;
  p:TGPPen;
begin
  g:=TGPGraphics.Create(Canvas.Handle);
  g.Clear(aclWhite);
  p:=TGPPen.Create(aclRed,2);

  g.DrawLine(p,20, 40, 200, 40);
  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)}

  p.Free;
  g.Free;
end;

end.