Title: Get MAC Address of Remote or Local Machine
Question: Function to return the MAC address of a remote or local machine in the format 'XX-XX-XX-XX-XX-XX'
The returned MAC address is a Unique ID that can be used in various ways. One way is as a parameter to my Wake On Lan function.(See article "http://www.delphi3000.com/articles/article_3847.asp")
Example :
ShowMessage(GetMacAddress('\\MHEYDON');
Output = '00-02-08-E7-99-6B'
Answer:
// ======================================================================
// Return the MAC address of Machine identified by AServerName
// Format of AServerName is '\\ServerName' or 'ServerName'
// If AServerName is a Null String then local machine MAC address
// is returned.
// Return string is in format 'XX-XX-XX-XX-XX-XX'
// ======================================================================
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;
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
// Silent Error
end;
end;
Result := Retvar;
end;