通过IP或机器名获取局域网MAC地址

通过IP获取局域网MAC地址

uses winsock; function sendarp(ipaddr:ulong;temp:dword;ulmacaddr:pointer;ulmacaddrleng:pointer) : Dword; StdCall;     External 'Iphlpapi.dll' Name 'SendARP'; function GetMACByIP(const Ip:string):string; var   MyIp:ulong;   MyMac:array[0..5] of byte;   MyMacLength:ulong;   ErrCode:integer; begin   Myip:=inet_addr(PChar(Ip));   MyMacLength:=Length(MyMac);   ErrCode:=SendArp(MyIp,0,@MyMac,@MyMacLength);   if ErrCode = 0 then      Result := Format('%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x',[MyMac[0],MyMac[1],MyMac[2],MyMac[3],MyMac[4],MyMac[5]])   else      Result := ''; //EorrCode: ErrCode end;
又一函数：
下面的函数以'XX-XX-XX-XX-XX-XX' 的格式返回远程或本地机器的MAC地址。

Function to return the MAC address of a remote or local machine in the format 'XX-XX-XX-XX-XX-XX'

返回的MAC地址是一个能用在多个方面的唯一标识。使用方法：
ShowMessage(GetMacAddress('//MHEYDON');
输出'00-02-08-E7-99-6B'// ====================================================================== //返回值是主机AServerName的MAC地址 //AServerName参数的格式为'//ServerName' 或者 'ServerName' //参数ServerName为空时返回本机的MAC地址 //MAC地址以'XX-XX-XX-XX-XX-XX'的格式返回 // ====================================================================== function GetMacAddress(const AServerName: string): string; type     TNetTransportEnum = function (pszServer: PWideChar;                                   Level: DWORD;                                   var pbBuffer: pointer;                                   PrefMaxLen: LongInt;                                   var EntriesRead: DWORD;                                   var TotalEntries: DWORD;                                   var ResumeHandle: DWORD): DWORD; stdcall;     TTransportInfo = record                       quality_of_service: DWord;                       number_of_vcs: DWORD;                       transport_name: PWChar;                       transport_address: PWChar;                       wan_ish: boolean;                     end;     TNetApiBufferFree = function(Buffer: pointer): DWORD; stdcall;     PTransportInfo = ^TTransportInfo; var     E,ResumeHandle,     EntriesRead,     TotalEntries: DWORD;     FLibHandle: THandle;     sMachineName,     sMacAddr,     Retvar: string;     pBuffer: pointer;     pInfo: PTransportInfo;     FNetTransportEnum: TNetTransportEnum;     FNetApiBufferFree: TNetApiBufferFree;     pszServer: array[0..128] of WideChar;     i,ii,iIdx: integer; begin   sMachineName := Trim(AServerName);   Retvar := '00-00-00-00-00-00';   //Add leading // if missing   if (sMachineName <> '') and (length(sMachineName) >= 2) then  begin     if copy(sMachineName,1,2) <> '//' then         sMachineName := '//' + sMachineName;   end;   //Setup and load from DLL   pBuffer := nil;   ResumeHandle := 0;   FLibHandle := LoadLibrary('NETAPI32.DLL');   // Execute the external function   if FLibHandle <> 0 then begin       @FNetTransportEnum := GetProcAddress(FLibHandle,'NetWkstaTransportEnum');       @FNetApiBufferFree := GetProcAddress(FLibHandle,'NetApiBufferFree');       E := FNetTransportEnum(StringToWideChar(sMachineName,pszServer,129),0,       pBuffer,-1,EntriesRead,TotalEntries,Resumehandle);     if E = 0 then begin       pInfo := pBuffer;       // Enumerate all protocols - look for TCPIP       for i := 1 to EntriesRead do begin           if pos('TCPIP',UpperCase(pInfo^.transport_name)) <> 0 then begin             // Got It - now format result 'xx-xx-xx-xx-xx-xx'             iIdx := 1;             sMacAddr := pInfo^.transport_address;             for ii := 1 to 12 do begin               Retvar[iIdx] := sMacAddr[ii];               inc(iIdx);               if iIdx in [3,6,9,12,15] then inc(iIdx);             end;         end;         inc(pInfo);       end;       if pBuffer <> nil then FNetApiBufferFree(pBuffer);     end;     try       FreeLibrary(FLibHandle);     except       // 错误处理     end;   end;   result:=Retvar; end;