如何检测端口是否被其它程序所占用？

bind的时候会报错的，判断返回值就可以了

try
    ss1.port:= 你需要测试的端口;
    ss1.open;
except
    showmessage('被占用');
end;

同意 sleepwalk(梦游)　我简单写了一下
uses WinSock;function checkPort(port:integer):boolean;
var
  err: Integer;
  sockHandle : WinSock.TSocket;
  WData: TWSAData;
  Addr: TSockAddr;
begin
  err := WSAStartup(MakeWord(2,2), WData);
  if err <> 0 then begin
     result := false;
     exit;
  end;

  sockHandle := socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
  if sockHandle = INVALID_SOCKET then begin
     //winsock创建失败
     result := false;
     exit;
  end;  Addr.sin_family := AF_INET;
  Addr.sin_port := htons(port); //端口号参数
  Addr.sin_addr.s_addr := INADDR_ANY;
  if bind(ServerSocketHandle, Addr, SizeOf(Addr)) = SOCKET_ERROR then begin
     //winsock绑定失败，可能是端口被占用
     result := false;
     exit;
  end;    result := true;//返回成功
  CloseSocket(sockHandle);
end;

ServerSocketHandle这个是什么，通不过，需要什么接口吗？

我从我的程序中copy&paste出来的，变量名错了，不好意思：）
uses WinSock;function checkPort(port:integer):boolean;
var
  err: Integer;
  sockHandle : WinSock.TSocket;
  WData: TWSAData;
  Addr: TSockAddr;
begin
  err := WSAStartup(MakeWord(2,2), WData);
  if err <> 0 then begin
    result := false;
    exit;
  end;

  sockHandle := socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
  if sockHandle = INVALID_SOCKET then begin
    //winsock创建失败
    result := false;
    exit;
  end;  Addr.sin_family := AF_INET;
  Addr.sin_port := htons(port); //端口号参数
  Addr.sin_addr.s_addr := INADDR_ANY;
  if bind(sockHandle , Addr, SizeOf(Addr)) = SOCKET_ERROR then begin
    //winsock绑定失败，可能是端口被占用
    result := false;
    exit;
  end;    result := true;//返回成功
  CloseSocket(sockHandle);
end;

如果你写扫描程序可千万不要这样,应该使用别的链接方法,否则你的踪迹会被别人
发现.例如使用sys扫描或者fin扫描:
我给你异步socket的api代码:
unit Unit1;
interface
uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls,WInSock, ExtCtrls;const WM_SOCKET=WM_USER+1;   //socket消息type
  TForm1 = class(TForm)
    Button1: TButton;
    Edit1: TEdit;
    Panel1: TPanel;
    Memo1: TMemo;
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    Sockhd : integer;   //socket句柄
    Serv_Addr : Tsockaddr;//目标地址  procedure SockEvent(var msg: Tmessage);message WM_SOCKET;   //处理cocket消息
  procedure DspMsg(msg : string);   //显示信息
    { Private declarations }
  public
    { Public declarations }
  end;  Form1: TForm1;implementation
{$R *.DFM}function lookup_hostname(const hostname:string):longint;  //把域名转化成IP地址
var
  RemoteHost : PHostEnt;  (* no, don't free it! *)
  ip_address: longint;
begin
  ip_address:=-1;
  try
    if hostname='' then
      begin  (* no host given! *)
        lookup_hostname:=ip_address;
        EXIT;
       end
    else
      begin
        ip_address:=Winsock.Inet_Addr(PChar(hostname));  (* try a xxx.xxx.xxx.xx first *)
        if ip_address=SOCKET_ERROR then begin
        RemoteHost:=Winsock.GetHostByName(PChar(hostname));
        if (RemoteHost=NIL) or (RemoteHost^.h_length<=0) then
          begin
            lookup_hostname:=ip_address;
            EXIT;  (* host not found *)
          end
        else
          ip_address:=longint(pointer(RemoteHost^.h_addr_list^)^);
      end;
      end;
   except
    ip_address:=-1;
  end;
  lookup_hostname:=ip_address;
end;procedure TFOrm1.DspMsg(msg: string);
begin
memo1.Lines.Add(msg+'...');
if Memo1.Lines.Count>200 then Memo1.Lines.Delete(0);
end;procedure TForm1.SockEvent(var msg : tmessage);  //处理socket消息
begin
case msg.LParam of
  FD_READ: begin    //标识可以读数据,当然肯定已经链接上了
    dspmsg('可以读取数据');
    //do what you want do
  end;  FD_WRITE: begin
    dspmsg('可以发送数据');
    //do what you want do
  end;  FD_ERROR: begin
    dspmsg('发生错误');
     //如果你是客户端,则应该是连接不上,即端口没有开
  end;  FD_CLOSE: Begin
    dspmsg('服务器断开连接');
    //对方关闭连接
  end;  FD_CONNECT: begin
    dspmsg('连结上服务器');
    //表示对方端口开放
  end;  FD_ACCEPT: begin
    dspmsg('接收一个请求');
   //这个消息只有服务端可能出现
  end;
end;
end;procedure TForm1.FormCreate(Sender: TObject);
var  wsaData:TwsaData;
begin                 //启动winsock动态链接库
  if WSAStartup (makeword(2,2), wsaData)<>0 then begin
    messagebox(application.handle,'无法启动winsock动态连接库!','警告',MB_OK or MB_APPLMODAL or MB_ICONWARNING);
    Application.Terminate;
  end;
end;procedure TForm1.FormDestroy(Sender: TObject);
begin    //关闭dll
WSACleanup;
end;procedure TForm1.Button1Click(Sender: TObject);
begin
Sockhd := socket(AF_INET,SOCK_STREAM,0);  //创建socket句柄
if Sockhd<0 then begin
   messagebox(application.handle,'无法创建句柄!','警告',MB_OK or MB_APPLMODAL or MB_ICONWARNING);
   exit;
end;
  Serv_addr.sin_addr.s_addr:= lookup_hostname(edit1.Text);  //主机名
  Serv_addr.sin_family := PF_INET;
  Serv_addr.sin_port := htons(23);      //any port you want to connect  if WSAAsyncSelect(Sockhd,Form1.handle,WM_SOCKET,FD_ACCEPT or FD_CONNECT or FD_CLOSE or  FD_READ or FD_WRITE)=SOCKET_ERROR
  then begin
   messagebox(application.handle,'无法创建句柄!','警告',MB_OK or MB_APPLMODAL or MB_ICONWARNING);
   exit;
  end;   //异步socket
  connect(sockhd,serv_addr,sizeof(serv_addr));  //连接,结果会在前面的处理函数处理
end;end.
相信应该可以满足你的要求

调试易

如何检测端口是否被其它程序所占用？

解决方案 »