/// <summary>
/// Parses an address. Returns false and sets the <paramref name="cidr"/> to null if the parse fails.
/// </summary>
/// <param name="address"></param>
/// <param name="cidr"></param>
/// <returns></returns>
public static bool TryParse(string address, out Cidr cidr)
{
var result = true;
try {
cidr = Parse(address);
} catch {
cidr = null;
result = false;
}
return(result);
}
/// <summary>
/// Creates a new object.
/// </summary>
/// <param name="cidr"></param>
public ByteArrayComparable(Cidr cidr)
{
if (cidr == null)
{
Array = _Empty;
}
else
{
var addressBytes = cidr.MaskedAddress.GetAddressBytes();
Array = new byte[addressBytes.Length + 1];
addressBytes.CopyTo(Array, 0);
Array[Array.Length - 1] = (byte)cidr.BitmaskBits;
}
}
/// <summary>
/// Parses an address. Throws exceptions if the parse fails.
/// </summary>
/// <param name="address"></param>
/// <returns></returns>
public static Cidr Parse(string address)
{
var result = new Cidr();
if (!String.IsNullOrEmpty(address))
{
// IPAddress.Parse is quite happy with addresses like "1" - this just makes sure that we
// have something that resembles a dotted-quad
if (address.Count(r => r == '.') != 3)
{
throw new ArgumentException("Invalid IPv4 address", "address");
}
var ipAddress = address;
var bitmask = 32;
var slashPosn = address.IndexOf('/');
if (slashPosn != -1)
{
ipAddress = address.Substring(0, slashPosn).Trim();
bitmask = int.Parse(address.Substring(slashPosn + 1));
}
if (bitmask < 0 || bitmask > 32)
{
throw new ArgumentOutOfRangeException("The number of bits must be between 0 and 32 inclusive");
}
result.BitmaskBits = bitmask;
var clearBits = 32 - bitmask;
while (bitmask-- != 0)
{
result.IPv4Bitmask = (result.IPv4Bitmask << 1) | 1;
}
result.IPv4Bitmask = result.IPv4Bitmask << clearBits;
result.Address = IPAddress.Parse(ipAddress);
if (result.Address.AddressFamily != AddressFamily.InterNetwork)
{
throw new InvalidOperationException("Only IPv4 addresses are currently supported");
}
result._MaskedAddressBytes = ApplyBitmask(result.Address, result.IPv4Bitmask);
result.MaskedAddress = new IPAddress(result._MaskedAddressBytes);
}
return(result);
}
