public static System.Net.IPAddress GetNetworkAddress(this System.Net.IPAddress address, System.Net.IPAddress subnetMask)
{
byte[] ipAdressBytes = address.GetAddressBytes();
byte[] subnetMaskBytes = subnetMask.GetAddressBytes();
if (ipAdressBytes.Length != subnetMaskBytes.Length)
{
throw new ArgumentException("Lengths of IP address and subnet mask do not match.");
}
byte[] broadcastAddress = new byte[ipAdressBytes.Length];
for (int i = 0; i < broadcastAddress.Length; i++)
{
broadcastAddress[i] = (byte)(ipAdressBytes[i] & (subnetMaskBytes[i]));
}
return(new System.Net.IPAddress(broadcastAddress));
}
public static bool IsIPv4LinkLocal(this System.Net.IPAddress address)
{
var addrBytes = address.GetAddressBytes();
return(address.AddressFamily == AddressFamily.InterNetwork && addrBytes[0] == 169 && addrBytes[1] == 254);
}
