利用DELPHI如何检测到网络的计算机上线与下线 ( 积分: 100 )

--bennykgd,
你的程序好像是来检测Internet连接状态的，好像不合楼主要求的“内网”

如下是我的测试代码，非常简陋，不过能够达到目的

废话：想不到Indy控件使用起来如此方便简单，呵呵，真是让人欣赏这高手所著的程序，同时也当然很感谢高手所作的系列Indy控件.

{*
  如下代码使用Ping来维护内网的计算机列表
  Win Xp +Delphi2005测试通过
               2005-4-24凌晨
}
unit Unit1;

...
type
  TForm1 = class(TForm)
    ListBox1: TListBox;
    Timer1: TTimer;
    IdIcmpClient1: TIdIcmpClient;
    procedure FormDblClick(Sender: TObject);
    procedure IdIcmpClient1Reply(ASender: TComponent;
      const AReplyStatus: TReplyStatus);
    procedure Timer1Timer(Sender: TObject);
...
var
  Form1: TForm1;

implementation

{$R *.dfm}
const
  ipHead :string ='192.168.0.';
procedure TForm1.Timer1Timer(Sender: TObject);
var
  i:Integer;
begin
  ListBox1.Clear;
  IdIcmpClient1.ReceiveTimeout :=1000;
  for i:=1 to 255 do
  begin
    IdIcmpClient1.Host :=ipHead +IntToStr(i);
    [red]IdIcmpClient1.Ping;[/red]
    Application.ProcessMessages;
  end;
end;

procedure TForm1.IdIcmpClient1Reply(ASender: TComponent;
  const AReplyStatus: TReplyStatus);
var
  sTime :string;
begin
  Caption :=IdIcmpClient1.Host;
  if [red][black]AReplyStatus.ReplyStatusType=rsEcho[/black][/red] then
  begin
    ListBox1.Items.Add(AReplyStatus.FromIpAddress);
  end;
end;

procedure TForm1.FormDblClick(Sender: TObject);
var
  i:Integer;
begin//仅仅为了自己测试
  ListBox1.Clear;
  IdIcmpClient1.ReceiveTimeout :=100;
  for i:=1 to 255 do
  begin
    IdIcmpClient1.Host :=ipHead +IntToStr(i);
    IdIcmpClient1.Ping;
    Application.ProcessMessages;
  end;
end;

end.