unit1.pas

Delphi7应用编程150例附书源码.rar

unit Unit1;

interface

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

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

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormPaint(Sender: TObject);
var
  x: Integer;
  y,a: Double;
begin
    Canvas.Pen.Width:=3;
    Canvas.MoveTo(0,Trunc(self.ClientHeight/2));
    for x := 0 to self.ClientWidth do
    begin
        a := (x/self.ClientWidth) * 2 * Pi;
        y := Sin(a);
        y := (1-y)*self.ClientHeight/2;
        Canvas.LineTo(Trunc(x), Trunc(y));
    end;
end;

procedure TForm1.FormResize(Sender: TObject);
begin
    Refresh;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
    self.DoubleBuffered:=true;
    //防止图形闪烁
end;

end.