VC 域名解析成ip地址

CString GetHostbyName(const char * HostName)
{
CString strIPAddress=_T("");
int WSA_return;
WSADATA WSAData;

WSA_return=WSAStartup(0x0202,&WSAData);
/* 结构指针 */
HOSTENT *host_entry;
if(WSA_return==0)
{
/* 即要解析的域名或主机名 */
host_entry=gethostbyname(HostName);
if(host_entry!=0)
{
strIPAddress.Format(_T("%d.%d.%d.%d"),
(host_entry->h_addr_list[0][0]&0x00ff),
(host_entry->h_addr_list[0][1]&0x00ff),
(host_entry->h_addr_list[0][2]&0x00ff),
(host_entry->h_addr_list[0][3]&0x00ff));
}
}
return strIPAddress;
}