Best way to create IPEndpoint from string
I had the requirement of parsing an IPEndpoint with IPv6, v4 and hostnames. The solution I wrote is listed below:
public static IPEndPoint Parse(string endpointstring)
{
return Parse(endpointstring, -1);
}
public static IPEndPoint Parse(string endpointstring, int defaultport)
{
if (string.IsNullOrEmpty(endpointstring)
|| endpointstring.Trim().Length == 0)
{
throw new ArgumentException("Endpoint descriptor may not be empty.");
}
if (defaultport != -1 &&
(defaultport < IPEndPoint.MinPort
|| defaultport > IPEndPoint.MaxPort))
{
throw new ArgumentException(string.Format("Invalid default port '{0}'", defaultport));
}
string[] values = endpointstring.Split(new char[] { ':' });
IPAddress ipaddy;
int port = -1;
//check if we have an IPv6 or ports
if (values.Length <= 2) // ipv4 or hostname
{
if (values.Length == 1)
//no port is specified, default
port = defaultport;
else
port = getPort(values[1]);
//try to use the address as IPv4, otherwise get hostname
if (!IPAddress.TryParse(values[0], out ipaddy))
ipaddy = getIPfromHost(values[0]);
}
else if (values.Length > 2) //ipv6
{
//could [a:b:c]:d
if (values[0].StartsWith("[") && values[values.Length - 2].EndsWith("]"))
{
string ipaddressstring = string.Join(":", values.Take(values.Length - 1).ToArray());
ipaddy = IPAddress.Parse(ipaddressstring);
port = getPort(values[values.Length - 1]);
}
else //[a:b:c] or a:b:c
{
ipaddy = IPAddress.Parse(endpointstring);
port = defaultport;
}
}
else
{
throw new FormatException(string.Format("Invalid endpoint ipaddress '{0}'", endpointstring));
}
if (port == -1)
throw new ArgumentException(string.Format("No port specified: '{0}'", endpointstring));
return new IPEndPoint(ipaddy, port);
}
private static int getPort(string p)
{
int port;
if (!int.TryParse(p, out port)
|| port < IPEndPoint.MinPort
|| port > IPEndPoint.MaxPort)
{
throw new FormatException(string.Format("Invalid end point port '{0}'", p));
}
return port;
}
private static IPAddress getIPfromHost(string p)
{
var hosts = Dns.GetHostAddresses(p);
if (hosts == null || hosts.Length == 0)
throw new ArgumentException(string.Format("Host not found: {0}", p));
return hosts[0];
}
This has been tested to work with the following examples:
- 0.0.0.0:100
- 0.0.0.0
- [::1]:100
- [::1]
- ::1
- [a:b:c:d]
- [a:b:c:d]:100
- example.org
- example.org:100
This is one solution...
public static IPEndPoint CreateIPEndPoint(string endPoint)
{
string[] ep = endPoint.Split(':');
if(ep.Length != 2) throw new FormatException("Invalid endpoint format");
IPAddress ip;
if(!IPAddress.TryParse(ep[0], out ip))
{
throw new FormatException("Invalid ip-adress");
}
int port;
if(!int.TryParse(ep[1], NumberStyles.None, NumberFormatInfo.CurrentInfo, out port))
{
throw new FormatException("Invalid port");
}
return new IPEndPoint(ip, port);
}
Edit: Added a version that will handle IPv4 and IPv6 the previous one only handles IPv4.
// Handles IPv4 and IPv6 notation.
public static IPEndPoint CreateIPEndPoint(string endPoint)
{
string[] ep = endPoint.Split(':');
if (ep.Length < 2) throw new FormatException("Invalid endpoint format");
IPAddress ip;
if (ep.Length > 2)
{
if (!IPAddress.TryParse(string.Join(":", ep, 0, ep.Length - 1), out ip))
{
throw new FormatException("Invalid ip-adress");
}
}
else
{
if (!IPAddress.TryParse(ep[0], out ip))
{
throw new FormatException("Invalid ip-adress");
}
}
int port;
if (!int.TryParse(ep[ep.Length - 1], NumberStyles.None, NumberFormatInfo.CurrentInfo, out port))
{
throw new FormatException("Invalid port");
}
return new IPEndPoint(ip, port);
}