public Connection(string historianServer, string instanceName)
{
if (string.IsNullOrEmpty(historianServer))
throw new ArgumentNullException(nameof(historianServer), "Missing historian server parameter");
if (string.IsNullOrEmpty(instanceName))
throw new ArgumentNullException(nameof(instanceName), "Missing historian instance name parameter");
string[] parts = historianServer.Split(':');
string hostName = parts[0];
int port;
if (parts.Length < 2 || !int.TryParse(parts[1], out port))
port = DefaultHistorianPort;
m_client = new HistorianClient(hostName, port);
m_instanceName = instanceName;
}