System.Net.Dns.GetHostEntry C# (CSharp) Метод

        public static IPHostEntry GetHostEntry(string hostNameOrAddress)
        {
            if (NetEventSource.IsEnabled) NetEventSource.Enter(null, hostNameOrAddress);
            NameResolutionPal.EnsureSocketsAreInitialized();

            if (hostNameOrAddress == null)
            {
                throw new ArgumentNullException(nameof(hostNameOrAddress));
            }

            // See if it's an IP Address.
            IPAddress address;
            IPHostEntry ipHostEntry;
            if (IPAddress.TryParse(hostNameOrAddress, out address))
            {
                if (address.Equals(IPAddress.Any) || address.Equals(IPAddress.IPv6Any))
                {
                    throw new ArgumentException(SR.Format(SR.net_invalid_ip_addr, nameof(hostNameOrAddress)));
                }

                ipHostEntry = InternalGetHostByAddress(address, true);
            }
            else
            {
                ipHostEntry = InternalGetHostByName(hostNameOrAddress, true);
            }

            if (NetEventSource.IsEnabled) NetEventSource.Exit(null, ipHostEntry);
            return ipHostEntry;
        }

    private static IPAddress Resolve(string hostName)
    {
        IPHostEntry he = Dns.GetHostEntry(hostName);

        if (he.AddressList.Length < 1)
        {
            throw new ApplicationException("IPHostEntry.AdressList is empty.");
        }
        return(he.AddressList[0]);
    }