/// <summary>
/// Establishes a connection to a remote host.
/// </summary>
/// <param name="remoteHostOrIp">A value containing the Hostname or IP address of the remote host.</param>
/// <param name="remotePort">A value indicating the port on the remote host to connect to.</param>
/// <param name="sslHost">The name of the host to validate the certificate for.</param>
/// <param name="localIp">A value indicating the IP address the client should connect from.</param>
/// <param name="localPort">A value indicating the port the client should connect from.</param>
public async void Connect(string remoteHostOrIp, int remotePort, string sslHost, string localIp, int localPort)
{
if (Parent.State != State.Closed)
{
throw new WinsockException("Cannot connect to a remote host when not Closed.");
}
/**
* First we need to make sure we have an IP address.
* If not - we need to try and resolve the fully qualified domain.
*/
Parent.ChangeState(State.ResolvingHost);
IPAddress resolvedRemoteIP = null, resolvedLocalIP = null;
if (!IPAddress.TryParse(remoteHostOrIp, out resolvedRemoteIP))
{
IPHostEntry entry = await Dns.GetHostEntryAsync(remoteHostOrIp);
if (entry == null || entry.AddressList.Length == 0)
{
string name = (entry != null) ? entry.HostName : remoteHostOrIp;
throw new WinsockException(string.Format("Hostname \"{0}\" could not be resolved.", name));
}
resolvedRemoteIP = entry.AddressList[0];
}
if (!string.IsNullOrWhiteSpace(localIp) && !IPAddress.TryParse(localIp, out resolvedLocalIP))
{
throw new WinsockException(string.Format("The value \"{0}\" is not a valid IP address for local binding.", localIp));
}
Parent.ChangeState(State.HostResolved);
/**
* Take our IP address and attempt to create the connection.
* Upon successfull connections - different BeginReceives could be called
* depending on if this was an attempt at a SECURE connection.
*/
IPEndPoint endPoint = new IPEndPoint(resolvedRemoteIP, remotePort);
IPEndPoint localEndPoint = (resolvedLocalIP != null) ? new IPEndPoint(resolvedLocalIP, localPort) : null;
socket = new AsyncSocket(endPoint.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
Parent.ChangeState(State.Connecting);
bool connectFail = false;
try
{
if (localEndPoint != null)
{
socket.Bind(localEndPoint);
}
await socket.ConnectAsync(endPoint);
}
catch (Exception ex)
{
connectFail = true;
Parent.ChangeState(State.Closed);
Parent.OnErrorReceived(Parent, ErrorReceivedEventArgs.Create(ex));
}
if (!connectFail)
{
Parent.ChangeState(State.Connected);
Parent.OnConnected(endPoint);
if (sslHost != null)
{
BeginReceive(false, sslHost);
}
else
{
BeginReceive(false);
}
}
}
