c# - 通过子网掩码计算IP范围

Question

如果我有子网掩码，例如255.255.255.0 和一个 IP 地址 192.168.1.5，是否有一种简单的方法来确定该子网中所有可能的 IP 地址？

在这种情况下:

192.168.1.1
192.168.1.2
192.168.1.3
192.168.1.4
...
...
192.168.1.252
192.168.1.253
192.168.1.254
192.168.1.255

到目前为止，我发现的都是重载的 .net 库。有没有使用默认 namespace 解决此问题的本地方法？

Answer 1

10 分钟的编码，未经过全面测试:

class IPSegment {

    private UInt32 _ip;
    private UInt32 _mask;

    public IPSegment(string ip, string mask) {
        _ip = ip.ParseIp();
        _mask = mask.ParseIp();
    }

    public UInt32 NumberOfHosts {
        get { return ~_mask+1; }
    }

    public UInt32 NetworkAddress {
        get { return _ip & _mask; }
    }

    public UInt32 BroadcastAddress {
        get { return NetworkAddress + ~_mask; }
    }

    public IEnumerable<UInt32> Hosts(){
        for (var host = NetworkAddress+1; host < BroadcastAddress; host++) {
            yield return  host;
        }
    }

}

public static class IpHelpers {
    public static string ToIpString(this UInt32 value) {
        var bitmask = 0xff000000;
        var parts = new string[4];
        for (var i = 0; i < 4; i++) {
            var masked = (value & bitmask) >> ((3-i)*8);
            bitmask >>= 8;
            parts[i] = masked.ToString(CultureInfo.InvariantCulture);
        }
        return String.Join(".", parts);
    }

    public static UInt32 ParseIp(this string ipAddress) {
        var splitted = ipAddress.Split('.');
        UInt32 ip = 0;
        for (var i = 0; i < 4; i++) {
            ip = (ip << 8) + UInt32.Parse(splitted[i]);
        }
        return ip;
    }
}

用法:

    static void Main(string[] args) {

        IPSegment ip = new IPSegment("192.168.1.1","255.255.255.248");

        Console.WriteLine(ip.NumberOfHosts);
        Console.WriteLine(ip.NetworkAddress.ToIpString());
        Console.WriteLine(ip.BroadcastAddress.ToIpString());

        Console.WriteLine("===");
        foreach (var host in ip.Hosts()) {
            Console.WriteLine(host.ToIpString());
        }
        Console.ReadLine();

    }