serversocket 绑定IP

Question

一个机子上有2张网卡,2个IP,用ServerSocket如何绑定其中一个呢

Answer 1

TServerSocket固定写死了绑定INADDR_ANY，就是本机的所有地址
要绑定的话要自己改tcp控件或者把ScktComp.pas重新修改编译一遍

Answer 2

unit Unit3;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ScktComp, StdCtrls;type
  TForm3 = class(TForm)    Button1: TButton;
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    procedure Button1Click(Sender: TObject);  private
    ServerSOcket1: TServerSocket;  public
    { Public declarations }
  end;  TMyServerSocket = class(TServerSocket)
    private
      FBindAddr: String;
    protected
      procedure ServerSocketEvent(Sender: TObject; Socket: TCustomWinSocket;
    SocketEvent: TSocketEvent);
    public
      property Address: String read FBindAddr write FBindAddr;
      constructor Create(AOwner: TComponent); override;
  end;
var
  Form3: TForm3;implementation
Uses
  Winsock;{$R *.dfm}function IsIP(const AHost:String):Boolean;
var
    iLen
  , I
  , TestDigit
  , DotCount: Integer;
    TestIP:   String;
begin
  Result := false;
  TestIP := AHost + '.';
  iLen := Length(AHost);
  if(iLen<7) or (iLen>15) then Exit;
  TestDigit := 0;
  DotCount := 0;
  for i := 1 to iLen + 1 do
    begin
      if(((TestIP[i] < '0') or (TestIP[i] > '9')) and ((TestIP[i] <> '.') or (i = 0))) then Exit;
      if(TestIP[i] = '.') then
      begin
         if (TestDigit > 255) or (TestDigit < 0) then Exit;
         if(TestIP[i-1] = '.') then Exit;
         TestDigit := 0;
         Inc(DotCount);
      end
      else
         TestDigit := TestDigit * 10 + (ord(TestIP[i]) - 48);
   end;
  Result := DotCount = 4;
end;function LocalGetHostByName(const AHost:String):String;
var
  WSAData: TWSADATA;
  Host:    PHostEnt;
begin
  Result := AHost;
  if(WSAStartup(MakeWord(1,1), WSAData) <> 0) then Exit;
  try
    Host := gethostbyname(PChar(AHost));
    Result := IntToStr(Byte(Host^.h_addr_list^[0])) + '.' +
              IntToStr(Byte(Host^.h_addr_list^[1])) + '.' +
              IntToStr(Byte(Host^.h_addr_list^[2])) + '.' +
              IntToStr(Byte(Host^.h_addr_list^[3]));
    if Not IsIP(Result) then Result:=AHost;
  finally
    WSACleanup;
  end;
end;function ResolveHost(const AHost: String): String;
begin
  Result := AHost;
  if AnsiSameText(AHost, 'LOCALHOST') or AnsiSameText(AHost, '(Local)') or AnsiSameText(AHost, '.') then   // this computer
    Result := '127.0.0.1'
  else if Not IsIP(Result) then
    Result := LocalGetHostByName(AHost);
end;constructor TMyServerSocket.Create(AOwner: TComponent);
begin
  Inherited Create(AOwner);
  FServerSocket.OnSocketEvent := ServerSocketEvent; //可以进行绑定的事件拦截事件
end;//拦载LookupState为lsIdle状态，替代为 lsLookupAddress，从而使用自定义的地址替代原来的INADDR_ANY
procedure TMyServerSocket.ServerSocketEvent(Sender: TObject; Socket: TCustomWinSocket;
    SocketEvent: TSocketEvent);
var
  Addr: TSockAddrIn;
  LookupState: TLookupState;
begin
  case SocketEvent of
    seLookup:
      begin
        if Socket.LookupState = lsIdle then
          begin
            if FBindAddr <> '' then //Hack Bind Address
              begin
                Addr := Socket.Addr;
                Addr.sin_addr.S_addr := inet_addr(PChar(ResolveHost(FBindAddr)));
                LookupState := lsLookupAddress;
                move( PChar(@Addr)^,
                      PChar(  Integer(Socket)                          //首地址 (4字节对齐)
                            + sizeof(Pointer)                          //虚函数表
                            + sizeof(TSocket)//FSocket: TSocket;       //占4字节
                            + sizeof(Pointer)//FConnected: Boolean;     //注意字节对齐,由于后续为4字节，虽只有1字节，但是占4字节
                            + sizeof(TStream)//FSendStream: TStream;    //占4字节
                            + sizeof(Pointer)//FDropAfterSend: Boolean; //注意字节对齐,由于后续为4字节，虽只有1字节，但是占4字节
                            + sizeof(HWnd)//FHandle: HWnd;              //占4字节
                            )^,
                      sizeof(TSockAddrIn));
                move( PChar(@LookupState)^,
                      PChar(  Integer(Socket)
                            + sizeof(Pointer)
                            + sizeof(TSocket)//FSocket: TSocket;
                            + sizeof(Pointer)//FConnected: Boolean;     //注意字节对齐
                            + sizeof(TStream)//FSendStream: TStream;
                            + sizeof(Pointer)//FDropAfterSend: Boolean; //注意字节对齐
                            + sizeof(HWnd)//FHandle: HWnd;
                            + sizeof(TSockAddrIn)//FAddr: TSockAddrIn;
                            + sizeof(TASyncStyles)//FAsyncStyles: TASyncStyles; //注意字节对齐
                            )^,
                      sizeof(TLookupState));
              end;          end;
      end;
  end;
end;procedure TForm3.Button1Click(Sender: TObject);
begin
  ServerSocket1.Open;
end;procedure TForm3.FormCreate(Sender: TObject);
begin
  ServerSocket1 := TMyServerSocket.Create(self);
  ServerSocket1.Port := 9999;
  TMyServerSocket(ServerSocket1).Address := '192.168.10.121';
  //事件处理过程列表
  //ServerSocket1.OnAccept := ...end;procedure TForm3.FormDestroy(Sender: TObject);
begin
  ServerSocket1.Free;
end;end.

Answer 3

前面的方法当中注意保存原来的FServerSocket.OnSocketEvent
unit Unit3;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ScktComp, StdCtrls;type
  TForm3 = class(TForm)    Button1: TButton;
    ServerSocket1: TServerSocket;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);  private
    FBindAddr: String;
    OldSocketEvent: TSocketEventEvent;
    procedure ServerSocketEvent(Sender: TObject; Socket: TCustomWinSocket;
    SocketEvent: TSocketEvent);
  public
    { Public declarations }
    property Address: String read FBindAddr write FBindAddr;
  end;var
  Form3: TForm3;implementation
Uses
  Winsock;{$R *.dfm}function IsIP(const AHost:String):Boolean;
var
    iLen
  , I
  , TestDigit
  , DotCount: Integer;
    TestIP:   String;
begin
  Result := false;
  TestIP := AHost + '.';
  iLen := Length(AHost);
  if(iLen<7) or (iLen>15) then Exit;
  TestDigit := 0;
  DotCount := 0;
  for i := 1 to iLen + 1 do
    begin
      if(((TestIP[i] < '0') or (TestIP[i] > '9')) and ((TestIP[i] <> '.') or (i = 0))) then Exit;
      if(TestIP[i] = '.') then
      begin
         if (TestDigit > 255) or (TestDigit < 0) then Exit;
         if(TestIP[i-1] = '.') then Exit;
         TestDigit := 0;
         Inc(DotCount);
      end
      else
         TestDigit := TestDigit * 10 + (ord(TestIP[i]) - 48);
   end;
  Result := DotCount = 4;
end;function LocalGetHostByName(const AHost:String):String;
var
  WSAData: TWSADATA;
  Host:    PHostEnt;
begin
  Result := AHost;
  if(WSAStartup(MakeWord(1,1), WSAData) <> 0) then Exit;
  try
    Host := gethostbyname(PChar(AHost));
    Result := IntToStr(Byte(Host^.h_addr_list^[0])) + '.' +
              IntToStr(Byte(Host^.h_addr_list^[1])) + '.' +
              IntToStr(Byte(Host^.h_addr_list^[2])) + '.' +
              IntToStr(Byte(Host^.h_addr_list^[3]));
    if Not IsIP(Result) then Result:=AHost;
  finally
    WSACleanup;
  end;
end;function ResolveHost(const AHost: String): String;
begin
  Result := AHost;
  if AnsiSameText(AHost, 'LOCALHOST') or AnsiSameText(AHost, '(Local)') or AnsiSameText(AHost, '.') then   // this computer
    Result := '127.0.0.1'
  else if Not IsIP(Result) then
    Result := LocalGetHostByName(AHost);
end;//拦载LookupState为lsIdle状态，替代为 lsLookupAddress，从而使用自定义的地址替代原来的INADDR_ANY
procedure TForm3.ServerSocketEvent(Sender: TObject; Socket: TCustomWinSocket;
    SocketEvent: TSocketEvent);
var
  Addr: TSockAddrIn;
  LookupState: TLookupState;
begin
  case SocketEvent of
    seLookup:
      begin
        if Socket.LookupState = lsIdle then
          begin
            if FBindAddr <> '' then //Hack Bind Address
              begin
                Addr := Socket.Addr;
                Addr.sin_addr.S_addr := inet_addr(PChar(ResolveHost(FBindAddr)));
                LookupState := lsLookupAddress;
                move( PChar(@Addr)^,
                      PChar(  Integer(Socket)                          //首地址 (4字节对齐)
                            + sizeof(Pointer)                          //虚函数表
                            + sizeof(TSocket)//FSocket: TSocket;       //占4字节
                            + sizeof(Pointer)//FConnected: Boolean;     //注意字节对齐,由于后续为4字节，虽只有1字节，但是占4字节
                            + sizeof(TStream)//FSendStream: TStream;    //占4字节
                            + sizeof(Pointer)//FDropAfterSend: Boolean; //注意字节对齐,由于后续为4字节，虽只有1字节，但是占4字节
                            + sizeof(HWnd)//FHandle: HWnd;              //占4字节
                            )^,
                      sizeof(TSockAddrIn));
                move( PChar(@LookupState)^,
                      PChar(  Integer(Socket)
                            + sizeof(Pointer)
                            + sizeof(TSocket)//FSocket: TSocket;
                            + sizeof(Pointer)//FConnected: Boolean;     //注意字节对齐
                            + sizeof(TStream)//FSendStream: TStream;
                            + sizeof(Pointer)//FDropAfterSend: Boolean; //注意字节对齐
                            + sizeof(HWnd)//FHandle: HWnd;
                            + sizeof(TSockAddrIn)//FAddr: TSockAddrIn;
                            + sizeof(TASyncStyles)//FAsyncStyles: TASyncStyles; //注意字节对齐
                            )^,
                      sizeof(TLookupState));
              end;          end;
      end;
  end;
  OldSocketEvent(Sender,Socket,SocketEvent);
end;procedure TForm3.Button1Click(Sender: TObject);
begin
  ServerSocket1.Open;
end;procedure TForm3.FormCreate(Sender: TObject);
begin
  ServerSocket1.Port := 9999;
  Address := '192.168.10.121';
  OldSocketEvent := ServerSocket1.Socket.OnSocketEvent;
  ServerSocket1.Socket.OnSocketEvent := ServerSocketEvent;
  if ServerSocket1.Active then
    begin
      ServerSocket1.Close;
      ServerSocket1.Active := False;
    end;
end;
end.

Answer 4

更正方法（在最后增加Event调用）：
//拦载LookupState为lsIdle状态，替代为 lsLookupAddress，从而使用自定义的地址替代原来的INADDR_ANY
procedure TMyServerSocket.ServerSocketEvent(Sender: TObject; Socket: TCustomWinSocket;
    SocketEvent: TSocketEvent);
var
  Addr: TSockAddrIn;
  LookupState: TLookupState;
begin
  case SocketEvent of
    seLookup:
      begin
        if Socket.LookupState = lsIdle then
          begin
            if FBindAddr <> '' then //Hack Bind Address
              begin
                Addr := Socket.Addr;
                Addr.sin_addr.S_addr := inet_addr(PChar(ResolveHost(FBindAddr)));
                LookupState := lsLookupAddress;
                move( PChar(@Addr)^,
                      PChar(  Integer(Socket)                          //首地址 (4字节对齐)
                            + sizeof(Pointer)                          //虚函数表
                            + sizeof(TSocket)//FSocket: TSocket;       //占4字节
                            + sizeof(Pointer)//FConnected: Boolean;     //注意字节对齐,由于后续为4字节，虽只有1字节，但是占4字节
                            + sizeof(TStream)//FSendStream: TStream;    //占4字节
                            + sizeof(Pointer)//FDropAfterSend: Boolean; //注意字节对齐,由于后续为4字节，虽只有1字节，但是占4字节
                            + sizeof(HWnd)//FHandle: HWnd;              //占4字节
                            )^,
                      sizeof(TSockAddrIn));
                move( PChar(@LookupState)^,
                      PChar(  Integer(Socket)
                            + sizeof(Pointer)
                            + sizeof(TSocket)//FSocket: TSocket;
                            + sizeof(Pointer)//FConnected: Boolean;     //注意字节对齐
                            + sizeof(TStream)//FSendStream: TStream;
                            + sizeof(Pointer)//FDropAfterSend: Boolean; //注意字节对齐
                            + sizeof(HWnd)//FHandle: HWnd;
                            + sizeof(TSockAddrIn)//FAddr: TSockAddrIn;
                            + sizeof(TASyncStyles)//FAsyncStyles: TASyncStyles; //注意字节对齐
                            )^,
                      sizeof(TLookupState));
              end;          end;
      end;
  end;  //增加这行代码
  Event(Socket,SocketEvent);
end;

Answer 5

系统有BUG，我也是……
退出之后再登录就行了