Is there native .NET type for CIDR subnets?

Question

It's simple enough to code up a class to store/validate something like 192.168.0.0/16, but I was curious if a native type for this already existed in .NET? I would imagine it would work a lot like IPAddress:

CIDR subnet = CIDR.Parse("192.168.0.0/16");

Basically it just needs to make sure you're working with an IPv4 or IPv6 address and then that the number of bits your specifying is valid for that type.

Answer 1

You can use the code from GitHub to do just that:

https://github.com/lduchosal/ipnetwork

IPNetwork ipnetwork = IPNetwork.Parse("192.168.168.100/24");

Console.WriteLine("Network : {0}", ipnetwork.Network);
Console.WriteLine("Netmask : {0}", ipnetwork.Netmask);
Console.WriteLine("Broadcast : {0}", ipnetwork.Broadcast);
Console.WriteLine("FirstUsable : {0}", ipnetwork.FirstUsable);
Console.WriteLine("LastUsable : {0}", ipnetwork.LastUsable);
Console.WriteLine("Usable : {0}", ipnetwork.Usable);
Console.WriteLine("Cidr : {0}", ipnetwork.Cidr);

Output

Network : 192.168.168.0
Netmask : 255.255.255.0
Broadcast : 192.168.168.255
FirstUsable : 192.168.168.1
LastUsable : 192.168.168.254
Usable : 254
Cidr : 24

Answer 2

No there is such native type in .NET, you will need to develop one your self.

Answer 3

For ASP.NET Core there is now IPNetwork class. Example usage below:

var addr = IPAddress.Parse("192.168.0.0");
var mask = 16;
var test = new IPNetwork(addr, mask).Contains(context.Connection.RemoteIpAddress);