把网线拔掉后，OS的IPCONFIG 为何还是能取到MAC值，而常见的D代码就不行了？(50分)

测试了一下，发现如题的现象。流行的D代码，在拔掉网线时，就返回空，但用OS 的
ipconfig命令在cmd下还是能显示原来的MAC
?

==代码==
uses
nb30;

type
PASTAT = ^TASTAT;
TASTAT = record
adapter : TAdapterStatus;
name_buf : TNameBuffer;
end;
function Getmac:string;
var
ncb : TNCB;
s:string;
adapt : TASTAT;
lanaEnum : TLanaEnum;
i, j, m : integer;
strPart, strMac : string;
begin
FillChar(ncb, SizeOf(TNCB), 0);
ncb.ncb_command := Char(NCBEnum);
ncb.ncb_buffer := PChar(@lanaEnum);
ncb.ncb_length := SizeOf(TLanaEnum);
s:=Netbios(@ncb);
for i := 0 to integer(lanaEnum.length)-1 do
begin
FillChar(ncb, SizeOf(TNCB), 0);
ncb.ncb_command := Char(NCBReset);
ncb.ncb_lana_num := lanaEnum.lana;
Netbios(@ncb);
Netbios(@ncb);
FillChar(ncb, SizeOf(TNCB), 0);
ncb.ncb_command := Chr(NCBAstat);
ncb.ncb_lana_num := lanaEnum.lana;
ncb.ncb_callname := '* ';
ncb.ncb_buffer := PChar(@adapt);
ncb.ncb_length := SizeOf(TASTAT);
m:=0;
if (Win32Platform = VER_PLATFORM_WIN32_NT) then
m:=1;
if m=1 then
begin
if Netbios(@ncb) = Chr(0) then
strMac := '';
for j := 0 to 5 do
begin
strPart := IntToHex(integer(adapt.adapter.adapter_address[j]), 2);
strMac := strMac + strPart + '-';
end;
SetLength(strMac, Length(strMac)-1);
end;
if m=0 then
if Netbios(@ncb) <> Chr(0) then
begin
strMac := '';
for j := 0 to 5 do
begin
strPart := IntToHex(integer(adapt.adapter.adapter_address[j]), 2);
strMac := strMac + strPart + '-';
end;
SetLength(strMac, Length(strMac)-1);
end;
end;
result:=strmac;
end;

function GetMAC: string;
var
Lib: Cardinal;
Func: function(GUID: PGUID): Longint; StdCall;
GUID1, GUID2: TGUID;
begin
try
Result := '';
Lib := LoadLibrary('rpcrt4.dll');
if Lib <> 0 then
begin
if Win32Platform <> VER_PLATFORM_WIN32_NT then
@Func := GetProcAddress(Lib, 'UuidCreate')
else @Func := GetProcAddress(Lib, 'UuidCreateSequential');
if Assigned(Func) then
begin
if (Func(@GUID1) = 0) and
(Func(@GUID2) = 0) and
(GUID1.D4[2] = GUID2.D4[2]) and
(GUID1.D4[3] = GUID2.D4[3]) and
(GUID1.D4[4] = GUID2.D4[4]) and
(GUID1.D4[5] = GUID2.D4[5]) and
(GUID1.D4[6] = GUID2.D4[6]) and
(GUID1.D4[7] = GUID2.D4[7]) then
begin
Result :=
IntToHex(GUID1.D4[2], 2) + '.' +
IntToHex(GUID1.D4[3], 2) + '.' +
IntToHex(GUID1.D4[4], 2) + '.' +
IntToHex(GUID1.D4[5], 2) + '.' +
IntToHex(GUID1.D4[6], 2) + '.' +
IntToHex(GUID1.D4[7], 2);
end;
end;
FreeLibrary(Lib);
end;
except
Result := '';
Application.ProcessMessages;
end;
end;


试试这个,网上以前的资源!

谢谢测试通过。用到了RPC。看来98下就不能用了。