获取整个局域网IP地址（同网段）

由于判断局域网IP地址是否合法用户，同时访问自己设定的网络服务（根据网络环境不同，可能部署的IP不同），使用下面方式轮询了局域网IP，通过页面进行显示，基本上能判定intranet的网络IP地址

DirectoryEntry root = new DirectoryEntry("WinNT:");

DirectoryEntries domains = root.Children;

domains.SchemaFilter.Add("domain");

foreach (DirectoryEntry domain in domains)

{

Response.Write("domain name: " + domain.Name + "<br>");

DirectoryEntries computers = domain.Children;

computers.SchemaFilter.Add("computer");

foreach (DirectoryEntry computer in computers)

{

Response.Write("computers name: " + computer.Name + "<br>");

string strcomputername = computer.Name;

try

{

IPHostEntry iphe = Dns.GetHostByName(strcomputername);

foreach (IPAddress ip in iphe.AddressList)

{

Response.Write("computers ip: " + ip + "<br>");

}

}

catch (Exception e)

{

//throw;

}

DirectoryEntries users = computer.Children;

}

}