unit code4;

interface

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

type
  TForm4 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    procedure Label3MouseMove(Sender: TObject; Shift: TShiftState; X,
      Y: Integer);
    procedure Label4MouseMove(Sender: TObject; Shift: TShiftState; X,
      Y: Integer);
    procedure Label3Click(Sender: TObject);
    procedure Label4Click(Sender: TObject);
    procedure FormMouseMove(Sender: TObject; Shift: TShiftState; X,
      Y: Integer);
    procedure FormPaint(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form4: TForm4;

implementation

{$R *.DFM}

procedure TForm4.Label3MouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
begin
  label3.Font.Color:=clred;
end;

procedure TForm4.Label4MouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
begin
 label4.Font.Color:=clred;
end;

procedure TForm4.Label3Click(Sender: TObject);
begin
 ShellExecute(GetDesktopWindow, 'open', 'mailto:ebugdoor@263.com', nil, nil, 0);
end;

procedure TForm4.Label4Click(Sender: TObject);
begin
 ShellExecute(GetDesktopWindow, 'open', 'http://xingsys.home.chinaren.com', nil, nil, 0);
end;

procedure TForm4.FormMouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
begin
  label3.Font.Color:=clLime;
  label4.font.Color:=clLime;
  label1.Font.Color:=clred;
  label2.Font.Color:=clred;
end;

procedure TForm4.FormPaint(Sender: TObject);
var
    i,j :integer;
    dct: TRect;
 begin
    j:=form4.Height;
    for i:=0 to 255 do
  begin   
    canvas.Brush.Color:=RGB(0,0,i);
    dct:=rect(i*2,0,(i+1)*2,j);
    canvas.FillRect(dct);
  end;
 end;
end.