C# And .dll’s

I’ve been working on Fizzure A LOT recently. I made a FizzSrvLight that is not a distributed system like the regular one, which therefore allowed me to write one effectively in about 3 hours. On the way I decided to make a few of my own methods and then realized, hey these can be used in other projects too!

So I made a class library (.dll – Dynamically Linked Library ) with a few methods that have to do with TCP Data transmition. The most important of which is the Send method that I made. Now this is really only useful for the client. Anyway, heres the snippet:


public static void Send(TcpClient Client, String Command)
{
Console.WriteLine("Opening Server Stream");
NetworkStream n = Client.GetStream();
String send = Command;
String receive = null;
byte[] msg = System.Text.Encoding.ASCII.GetBytes(send);
n.Write(msg, 0, msg.Length);
Console.WriteLine("SENT: {0}", send);
}

this method is meant for console programs, but if you are using a GUI all you really need to do is delete the Console.WriteLines()’s in there and replace it with wherever you want the output.

Hope this is helpful to everyone!

C# TcpListener Example

Ok, this is just a quick snippet of code I wrote to get a working server up. Obviously theres more commands I could put in there in plenty of different ways, but I really just wanted to keep things simple for now. This took me about 2 hours.

This snippet is the main body of code that controls everything. If you go through it and read you’ll see that I made a struct to hold the information on files named File, in the namespace Structure. So you would access it by saying in this [MainNamespace].Structure.File; or you can just use Structure.File. I’ll paste the code for the struct at the end.

I didn’t leave too many comments because I used a lot of Writelines to tell me what it was doing, and for debugging purposes. Those kind of tell you what things do what.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text;

namespace FizzSrvLight
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine(“FizzSrvLight :: Non-Distributed Fizzure Serving Capabilities”);
System.Threading.Thread.Sleep(1000);
Console.Write(“Loading…”);
Console.WriteLine(“!”);

Console.WriteLine(“Initiating Server Variables…”);
System.Net.IPAddress localaddr = System.Net.IPAddress.Parse(“127.0.0.1″);

Console.WriteLine(“Constructing Server Objects…”);
System.Net.Sockets.TcpListener MainServer = new System.Net.Sockets.TcpListener(localaddr, 9000);

Console.WriteLine(“Starting Server…”);
MainServer.Start();

Byte[] bytes = new Byte[1024];
String data = null;
String send = null;

while (true)
{
Console.WriteLine(“Waiting for connection…”);

// Accept Requests
System.Net.Sockets.TcpClient client = MainServer.AcceptTcpClient();
Console.WriteLine(“Client Connected!”);

// Clear Buffers
data = null;
send = null;

// Get Stream Object for reading and writing
System.Net.Sockets.NetworkStream stream = client.GetStream();

int i;

// Initialize File Holder
System.Collections.ArrayList CurrentFiles = new System.Collections.ArrayList();

// Loop to recieve all data sent from client
while ((i = stream.Read(bytes, 0, bytes.Length)) != 0)
{
// Clear buffers again
data = null;
send = null;
string message = “OK”;
// Get data as string
data = System.Text.Encoding.ASCII.GetString(bytes, 0, i);
Console.WriteLine(“FIZZ_RCV: {0}”, data);

String[] command = data.Split(‘ ‘);

// Insert Possible Commands Here
if (command[0] == “FIZZ_ADDFILE”)
{
FizzSrvLight.Structure.File file = new FizzSrvLight.Structure.File(command[1], command[2], command[3], command[4], command[5], command[6]);
CurrentFiles.Add(file);
}
else if (command[0] == “FIZZ_RMVFILE”)
{
FizzSrvLight.Structure.File file = new FizzSrvLight.Structure.File(command[1], command[2], command[3], command[4], command[5], command[6]);
CurrentFiles.Remove(file);
}
else if (command[0] == “FIZZ_AUTH”)
{
string username = command[1];
string password = command[2];
}
else
{
Console.WriteLine(“FIZZ_INVALID_INPUT”);
Console.WriteLine(“Error Handled”);
message = “ERROR”;
}

send = message;

byte[] msg = System.Text.Encoding.ASCII.GetBytes(send);

// Send back an OK response;
stream.Write(msg, 0, msg.Length);
Console.WriteLine(“FIZZ_SND: ” + message);
}
System.Threading.Thread.Sleep(1000);
}
}
}
}

Now, time for the struct.

namespace FizzSrvLight
{
namespace Structure
{
public struct File
{
public string FileName;
public string FilePath;
public string FileType;
public string SharedBy;
public string IPAddress;
public string Blacklist;

public File(string name, string path, string type, string user, string ipaddr, string blacklisted)
{
FileName = name;
FilePath = path;
FileType = type;
SharedBy = user;
IPAddress = ipaddr;
Blacklist = blacklisted;
}

}
}
}

Well, there you have it. A very simple TcpListener Serve. Obviously theres better ways to do it but this is pretty simple, straight forward, and just all around easy. Please leave comments if you find bugs in it or see errors or even if you just don’t understand what some of it does.