再学 GDI+[8] DrawRectangles - 绘制一组矩形

 

unit Unit1;

interface

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

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

var
  Form1: TForm1;

implementation

{$R *.dfm}
uses
  GDIPOBJ,GDIPAPI;
var
  RectArr:array[0..31] of TGPRect; //声明矩形数组
procedure TForm1.FormPaint(Sender: TObject);
var
  g:TGPGraphics;
  p:TGPPen;
begin
  form1.DoubleBuffered:=True; //双缓冲开启就没那么闪烁了
  g:=TGPGraphics.Create(Canvas.Handle);
  g.Clear(aclWhite);
  p:=TGPPen.Create(aclRed,2);

  g.DrawRectangles(p,PGPRect(@RectArr),Length(RectArr)); //根据矩形数组画一组矩形
  p.Free;
  g.Free;
end;

procedure TForm1.FormResize(Sender: TObject);
var
  wi,hi,i:Integer;
  rect:TGPRect;
begin
  rect.X:=0;
  rect.Y:=0;
  rect.Width:=ClientWidth;
  rect.Height:=ClientHeight;

  wi:=rect.Width div Length(RectArr);  //计算32个矩形宽高的平均间距
  hi:=rect.Height div Length(RectArr);

  for I := 0 to Length(RectArr) - 1 do   //通过间距求出每一个矩形的坐标和宽高，并保存到数组中;
    begin
      inc(rect.X,wi);
      inc(rect.Y,hi);
      Dec(rect.Width,wi*2);   //因为坐标值是由0而不是1开始的，因此坐标XY加一份平均间距，宽高就要减两份
      Dec(rect.Height,hi*2);
      RectArr[i]:=rect;       //保存到数组
    end;
  Repaint;
end;

end.