1、通过IP取MAC地址

uses
WinSock;

Function sendarp(ipaddr:ulong;
temp:dword;
ulmacaddr:pointer;
ulmacaddrleng:pointer) : DWord; StdCall; External 'Iphlpapi.dll' Name 'SendARP';

procedure TForm1.Button1Click(Sender: TObject);
var
myip:ulong;
mymac:array[0..5] of byte;
mymaclength:ulong;
r:integer;
begin
myip:=inet_addr(PChar('192.168.6.180'));
mymaclength:=length(mymac);
r:=sendarp(myip,0,@mymac,@mymaclength);
label1.caption:='errorcode:'+inttostr(r);
label2.caption:=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]]);
end; 


2、取MAC地址 （含多网卡）,最好的方法，支持Vista,Win7

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
WinSock, StdCtrls;

Const
MAX_HOSTNAME_LEN = 128; { from IPTYPES.H }
MAX_DOMAIN_NAME_LEN = 128;
MAX_SCOPE_ID_LEN = 256;
MAX_ADAPTER_NAME_LENGTH = 256;
MAX_ADAPTER_DESCRIPTION_LENGTH = 128;
MAX_ADAPTER_ADDRESS_LENGTH = 8;

Type
TIPAddressString = Array[0..4*4-1] of Char;

PIPAddrString = ^TIPAddrString;
TIPAddrString = Record
Next : PIPAddrString;
IPAddress : TIPAddressString;
IPMask : TIPAddressString;
Context : Integer;
End;

PFixedInfo = ^TFixedInfo;
TFixedInfo = Record { FIXED_INFO }
HostName : Array[0..MAX_HOSTNAME_LEN+3] of Char;
DomainName : Array[0..MAX_DOMAIN_NAME_LEN+3] of Char;
CurrentDNSServer : PIPAddrString;
DNSServerList : TIPAddrString;
NodeType : Integer;
ScopeId : Array[0..MAX_SCOPE_ID_LEN+3] of Char;
EnableRouting : Integer;
EnableProxy : Integer;
EnableDNS : Integer;
End;

PIPAdapterInfo = ^TIPAdapterInfo;
TIPAdapterInfo = Record { IP_ADAPTER_INFO }
Next : PIPAdapterInfo;
ComboIndex : Integer;
AdapterName : Array[0..MAX_ADAPTER_NAME_LENGTH+3] of Char;
Description : Array[0..MAX_ADAPTER_DESCRIPTION_LENGTH+3] of Char;
AddressLength : Integer;
Address : Array[1..MAX_ADAPTER_ADDRESS_LENGTH] of Byte;
Index : Integer;
_Type : Integer;
DHCPEnabled : Integer;
CurrentIPAddress : PIPAddrString;
IPAddressList : TIPAddrString;
GatewayList : TIPAddrString;
DHCPServer : TIPAddrString;
HaveWINS : Bool;
PrimaryWINSServer : TIPAddrString;
SecondaryWINSServer : TIPAddrString;
LeaseObtained : Integer;
LeaseExpires : Integer;
End;

type
TForm1 = class(TForm)
Button1: TButton;
Memo1: TMemo;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
procedure GetAdapterInformation;
public
{ Public declarations }
end;

var
Form1: TForm1;

Function sendarp(ipaddr:ulong;
temp:dword;
ulmacaddr:pointer;
ulmacaddrleng:pointer) : DWord; StdCall;

implementation

{$R *.dfm}

Function sendarp; External 'Iphlpapi.dll' Name 'SendARP';
Function GetAdaptersInfo(AI : PIPAdapterInfo; Var BufLen : Integer) : Integer;
StdCall; External 'iphlpapi.dll' Name 'GetAdaptersInfo';

procedure TForm1.GetAdapterInformation;
Var
AI,Work : PIPAdapterInfo;
Size : Integer;
Res : Integer;
I : Integer;

Function MACToStr(ByteArr : PByte; Len : Integer) : String;
Begin
Result := '';
While (Len > 0) do Begin
Result := Result+IntToHex(ByteArr^,2)+'-';
ByteArr := Pointer(Integer(ByteArr)+SizeOf(Byte));
Dec(Len);
End;
SetLength(Result,Length(Result)-1); { remove last dash }
End;

Function GetAddrString(Addr : PIPAddrString) : String;
Begin
Result := '';
While (Addr <> nil) do Begin
Result := Result+'A: '+Addr^.IPAddress+' M: '+Addr^.IPMask+#13;
Addr := Addr^.Next;
End;
End;

Function TimeTToDateTimeStr(TimeT : Integer) : String;
Const UnixDateDelta = 25569; { days between 12/31/1899 and 1/1/1970 }
Var
DT : TDateTime;
TZ : TTimeZoneInformation;
Res : DWord;

Begin
If (TimeT = 0) Then Result := ''
Else Begin
{ Unix TIME_T is secs since 1/1/1970 }
DT := UnixDateDelta+(TimeT / (24*60*60)); { in UTC }
{ calculate bias }
Res := GetTimeZoneInformation(TZ);
If (Res = TIME_ZONE_ID_INVALID) Then RaiseLastWin32Error;
If (Res = TIME_ZONE_ID_STANDARD) Then Begin
DT := DT-((TZ.Bias+TZ.StandardBias) / (24*60));
Result := DateTimeToStr(DT)+' '+WideCharToString(TZ.StandardName);
End
Else Begin { daylight saving time }
DT := DT-((TZ.Bias+TZ.DaylightBias) / (24*60));
Result := DateTimeToStr(DT)+' '+WideCharToString(TZ.DaylightName);
End;
End;
End;

begin
Memo1.Lines.Clear;
Size := 5120;
GetMem(AI,Size);
Res := GetAdaptersInfo(AI,Size);
If (Res <> ERROR_SUCCESS) Then Begin
SetLastError(Res);
RaiseLastWin32Error;
End;
With Memo1,Lines do Begin
Work := AI;
I := 1;
Repeat
Add('');
Add('Adapter ' + IntToStr(I));
Add(' ComboIndex: '+IntToStr(Work^.ComboIndex));
Add(' Adapter name: '+Work^.AdapterName);
Add(' Description: '+Work^.Description);
Add(' Adapter address: '+MACToStr(@Work^.Address,Work^.AddressLength));
Add(' Index: '+IntToStr(Work^.Index));
Add(' Type: '+IntToStr(Work^._Type));
Add(' DHCP: '+IntToStr(Work^.DHCPEnabled));
Add(' Current IP: '+GetAddrString(Work^.CurrentIPAddress));
Add(' IP addresses: '+GetAddrString(@Work^.IPAddressList));
Add(' Gateways: '+GetAddrString(@Work^.GatewayList));
Add(' DHCP servers: '+GetAddrString(@Work^.DHCPServer));
Add(' Has WINS: '+IntToStr(Integer(Work^.HaveWINS)));
Add(' Primary WINS: '+GetAddrString(@Work^.PrimaryWINSServer));
Add(' Secondary WINS: '+GetAddrString(@Work^.SecondaryWINSServer));
Add(' Lease obtained: '+TimeTToDateTimeStr(Work^.LeaseObtained));
Add(' Lease expires: '+TimeTToDateTimeStr(Work^.LeaseExpires));
Inc(I);
Work := Work^.Next;
Until (Work = nil);
End;
FreeMem(AI);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
GetAdapterInformation;
end;

end.



方法3 我没试成功

uses nb30;

function NBGetAdapterAddress(a: Integer): string;
var
NCB: TNCB; // Netbios control block //NetBios控制块
ADAPTER: TADAPTERSTATUS; // Netbios adapter status//取网卡状态
LANAENUM: TLANAENUM; // Netbios lana
intIdx: Integer; // Temporary work value//临时变量
cRC: Char; // Netbios return code//NetBios返回值
strTemp: string; // Temporary string//临时变量
begin
Result := '';

try
ZeroMemory(@NCB, SizeOf(NCB)); // Zero control blocl

NCB.ncb_command := Chr(NCBENUM); // Issue enum command
cRC := NetBios(@NCB);

NCB.ncb_buffer := @LANAENUM; // Reissue enum command
NCB.ncb_length := SizeOf(LANAENUM);
cRC := NetBios(@NCB);
if Ord(cRC) <> 0 then
exit;

ZeroMemory(@NCB, SizeOf(NCB)); // Reset adapter
NCB.ncb_command := Chr(NCBRESET);
NCB.ncb_lana_num := LANAENUM.lana[a];
cRC := NetBios(@NCB);
if Ord(cRC) <> 0 then
exit;


ZeroMemory(@NCB, SizeOf(NCB)); // Get adapter address
NCB.ncb_command := Chr(NCBASTAT);
NCB.ncb_lana_num := LANAENUM.lana[a];
StrPCopy(NCB.ncb_callname, '*');
NCB.ncb_buffer := @ADAPTER;
NCB.ncb_length := SizeOf(ADAPTER);
cRC := NetBios(@NCB);

strTemp := ''; // Convert it to string
for intIdx := 0 to 5 do
strTemp := strTemp + InttoHex(Integer(ADAPTER.adapter_address[intIdx]), 2);
Result := strTemp;
finally
end;
end; 

 方法4：当前活动的网卡地址(Vista下可能取不到)

// ======================================================================
//返回值是主机AServerName的MAC地址
//AServerName参数的格式为\\ 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 GetMacAddress2(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;

     TNetApiBufferFree = function(Buffer : pointer) : DWORD; stdcall;

     PTransportInfo = ^TTransportInfo; 
     TTransportInfo = record 
                       quality_of_service : DWORD; 
                       number_of_vcs : DWORD; 
                       transport_name : PWChar; 
                       transport_address : PWChar; 
                       wan_ish : boolean; 
                     end;

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;