如何获得本机所有Ip地址的子网掩码？(50分)

如题？
在大富翁，我怎么不能搜索了？

通过注册表。别无它法。

unit USock;

interface

uses Windows, Winsock;
{
使用到WinSock2。
这是一个完整的Delphi单元，将它加入到你的工程中，你可以调用：
EnumInterfaces(var s string): Boolean;
来返回所有IP地址、网络掩码、广播地址和连接状态。

此函数列举出所有的TCP/IP连接，并返回一个由回车换行(CRLF)符分隔的字符串，包含以下信息：
IP, NetMask, BroadCast-Address, Up/Down status,
Broadcast support, Loopback
如果你将这个字符串赋给TMemo(它的Memo.Lines.Text属性)，你可以看到更清晰的结果。
使用此函数，你需要Win98/ME/2K, 95 OSR 2 或者NT service pack #3，
因为程序会使用到WinSock 2(WS2_32.DLL)。}

function EnumInterfaces(var sInt: string): Boolean;

{从Winsock 2.0导入函数WSAIOCtl -- 在Win98/ME/2K and 95 OSR2, NT srv pack #3下才有Winsock 2}
function WSAIoctl(s: TSocket; cmd: DWORD; lpInBuffer: PCHAR; dwInBufferLen: DWORD;
lpOutBuffer: PCHAR; dwOutBufferLen: DWORD;
lpdwOutBytesReturned: LPDWORD;
lpOverLapped: POINTER;
lpOverLappedRoutine: POINTER): Integer; stdcall; external 'WS2_32.DLL';

{Constants taken from C header files}
const
SIO_GET_INTERFACE_LIST = $4004747F;
IFF_UP = $00000001;
IFF_BROADCAST = $00000002;
IFF_LOOPBACK = $00000004;
IFF_POINTTOPOINT = $00000008;
IFF_MULTICAST = $00000010;

type
sockaddr_gen = packed record
AddressIn: sockaddr_in;
filler: packed array[0..7] of char;
end;

type
INTERFACE_INFO = packed record
iiFlags: u_long; // Interface flags
iiAddress: sockaddr_gen; // Interface address
iiBroadcastAddress: sockaddr_gen; // Broadcast address
iiNetmask: sockaddr_gen; // Network mask
end;

implementation

{
1. 打开Winsock
2. 创建一个socket
3. 调用WSAIOCtl获取网络连接
4. 对每个连接，获取它的IP、掩码、广播地址、状态
5. 将信息填充到一个由CDLF分隔的字符串中
6. 结束}



function EnumInterfaces(var sInt: string): Boolean;
var
s: TSocket;
wsaD: WSADATA;
NumInterfaces: Integer;
BytesReturned, SetFlags: u_long;
pAddrInet: SOCKADDR_IN;
pAddrString: PCHAR;
PtrA: pointer;
Buffer: array[0..20] of INTERFACE_INFO;
i: Integer;
begin
result := true; // Initialize
sInt := '';
WSAStartup($0101, wsaD); // Start WinSock
// You should normally check
// for errors here
s := Socket(AF_INET, SOCK_STREAM, 0); // Open a socket
if (s = INVALID_SOCKET) then exit;

try // Call WSAIoCtl
PtrA := @bytesReturned;
if (WSAIoCtl(s, SIO_GET_INTERFACE_LIST, nil, 0, @Buffer, 1024, PtrA, nil,
nil)
<> SOCKET_ERROR) then
begin // If ok, find out how
// many interfaces exist

NumInterfaces := BytesReturned div SizeOf(INTERFACE_INFO);

for i := 0 to NumInterfaces - 1 do // For every interface
begin
pAddrInet := Buffer.iiAddress.addressIn; // IP ADDRESS
pAddrString := inet_ntoa(pAddrInet.sin_addr);
sInt := sInt + ' IP=' + pAddrString + ',';
pAddrInet := Buffer.iiNetMask.addressIn; // SUBNET MASK
pAddrString := inet_ntoa(pAddrInet.sin_addr);
sInt := sInt + ' Mask=' + pAddrString + ',';
pAddrInet := Buffer.iiBroadCastAddress.addressIn; // Broadcast addr
pAddrString := inet_ntoa(pAddrInet.sin_addr);
sInt := sInt + ' Broadcast=' + pAddrString + ',';

SetFlags := Buffer.iiFlags;
if (SetFlags and IFF_UP) = IFF_UP then
sInt := sInt + ' Interface UP,' // Interface up/down
else
sInt := sInt + ' Interface DOWN,';

if (SetFlags and IFF_BROADCAST) = IFF_BROADCAST then // Broadcasts
sInt := sInt + ' Broadcasts supported,' // supported or
else // not supported
sInt := sInt + ' Broadcasts NOT supported,';
if (SetFlags and IFF_LOOPBACK) = IFF_LOOPBACK then // Loopback or
sInt := sInt + ' Loopback interface'
else
sInt := sInt + ' Network interface'; // normal
sInt := sInt + #13#10; // CRLF between
// each interface
end;
end;
except
end;
//
// Close sockets
//
CloseSocket(s);
WSACleanUp;
result := false;
end;

end.

另外 通过注册表
HKEY_LOCAL_MACHINE/System/CurrentControlSet/
Services/Class/NetTrans/中得到。
搜索从0001到000a,如果
DriverDesc =TCP/IP,则IPMask就是当前掩码