C＃包结构系统

Question

I am working on a packet system (UDP or TCP, either way is fine) but I came to the conclusion that my current (TCP) system is really awefull.

Basicly, I'm sending a packet that looks like this:

string packet = "LOGIN_AUTH;TRUE"
IPAddress target = IPAddress.Parse(endPoint);
// Send packet

When I recieve the packet in my client, I use this to determine the packet type:

string[] splitPacket = packet.Split(';');

if (splitPacket[0] == "LOGIN_AUTH" && splitPacket[1] == "TRUE")
   authLogin(packet); //Does stuff like loading the next screen

But I'm sure there must be a better way to do this, because of this thread:

http://social.msdn.microsoft.com/forums/en-US/netfxnetcom/thread/79660898-aeee-4c7b-8cba-6da55767daa1/ (post 2)

I'm just wondering if someone could give me a push in the right direction on what I should to categorize the packets in a way that's more easy on the eye.

Thank you in advance.

Edit: I did some research, but I cant find a solution to my problem in WCF. So once again, what is the best way to create a packet structure, and how do I utilize it?

I don't want to recreate a protocol, just something like this:

public string sepChar = ";"
public static struct loginPacket
{
    string type;
    string username;
    string password;
}

public void reqLogin()
{
    lock (_locker)      //Need to make it thread-safe in this case
    {
         loginPacket.type = "login";
         loginPacket.username = "username";
         loginPacket.password = "password;

         sendPacket(loginPacket);
    }
}

public void sendPacket(string packet)
{
    // Script to send packet using the struct information
}

I hope that's detailed enough.

Answer 1

I would recommend WCF; if not now, decide to learn it in the future. It has a huge learning curve because it covers not only what you're trying to do, but so many other things.

If you just want a quick-and-dirty solution, then you could use binary serialization. To take this approach, you'll need to define your message types in a dll shared between client and server. Then, remember to use a form of message framing so that the messages don't get munged up in transit.

Things get more complex when you consider versioning. Eventually you'll want to use WCF.

Answer 2

I have used my own communication protocol over TCP 2 years ago, about the base packet class:

public enum PacketType {Login, Hello, FooBar}
public class Packet
{
    public long Size;
    public PacketType PacketType;
}
public class LoginPacket : Packet
{
    public string Login;
    public string Password;
}

I do not agree with Size property... because you will only know packet size AFTER it was serialized with binaryFormater. I have used other method, first i serialized packet object and then before putting this byte[] in network stream i wrote BitConverter.GetBytes(SerializedPacketMemoryStream.Length) before each packet bytes.
2nd thing to consider, is that you need to create temp buffer for received bytes[] and wait until you receive full packet and only then desirialize it.
I can send you my client\\server code part, it's not very clean i wrote it when i just started learning C#, but it is 100% stable, tested for 3 years in production environment.

Answer 3

protobuf might be what you want.

Here's the .NET port: protobuf-net