ClientMainForm.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Net;
using System.Net.Sockets;
using System.IO;

namespace Client
{
    public partial class ClientMainForm : Form
    {
        TcpClient client = new TcpClient();
        public ClientMainForm()
        {
            InitializeComponent();

            Connect();
        }

        private void Connect()
        {

            //try to connect since it's not connected...
            try
            {
                client = new TcpClient("127.0.0.1", 3030);
                client.GetStream().BeginRead(new Byte[] {0}, 0, 0, new AsyncCallback(Read), null);

            }
            catch (Exception)
            {
                //wait 1 second till trying again
                System.Threading.Thread.Sleep(1000);
                Connect();
            }

        }

        private void Read(IAsyncResult ar)
        {
            try
            {
                using (NetworkStream stream = client.GetStream())
                {
                    if (stream.CanRead)
                    {
                        byte[] buffer = new byte[client.ReceiveBufferSize];
                        int bytesRead = stream.Read(buffer, 0, buffer.Length);
                        //reads the buffer as a string for a command...
                        string message = Encoding.UTF8.GetString(buffer);
                        Console.WriteLine("data from client: " + message);

                        string[] messageParts = message.Split(Shared.Separator);

                        switch (messageParts[0])
                        {
                            case Shared.Message:
                                Console.WriteLine(messageParts[1]);
                                //MessageBox.Show(messageParts[1]);
                                break;
                            case Shared.FileRecieve:
                                Console.WriteLine("FileRecieve Message");
                                FileRecieve(messageParts[1], messageParts[2], buffer);

                                break;

                        }
                    }


                }



                client.GetStream().BeginRead(new byte[] { 0 }, 0, 0, Read, null);

            }
            catch (Exception)
            {
                //error occured tell the server that this client exited...
                Connect();
            }
        }


        private void FileRecieve(string FileName, string FileSize, byte[] InitialBuffer)
        {
            NetworkStream NS = client.GetStream();

            // Check to see if this NetworkStream is readable.
            if (NS.CanRead)
            {

                byte[] fileInfo = new byte[FileName.Length + FileSize.Length + 2];

                byte[] myReadBuffer = new byte[1024];
                byte[] myCompleteMessage = new byte[Convert.ToInt32(FileSize)];
                int numberOfBytesRead = 0;
                int totalBytesRead = 0;

                //gets the initial buffer file data and puts it into the completed message...
                Array.ConstrainedCopy(InitialBuffer, fileInfo.Length, myCompleteMessage, 0, InitialBuffer.Length - fileInfo.Length);
                totalBytesRead += InitialBuffer.Length - fileInfo.Length;
                // Incoming message may be larger than the buffer size.

                do
                {
                    numberOfBytesRead = NS.Read(myReadBuffer, 0, myReadBuffer.Length);
                    totalBytesRead += numberOfBytesRead;
                    Array.ConstrainedCopy(myReadBuffer, 0, myCompleteMessage, totalBytesRead, myReadBuffer.Length);

                }
                while (NS.DataAvailable);

                // Print out the received message to the console.
                Console.WriteLine("You received the following message : " + myCompleteMessage);
                FileStream FS = new FileStream(FileName, FileMode.Create);
                FS.Write(myCompleteMessage, 0, myCompleteMessage.Length);

            }
            else
            {
                Console.WriteLine("Sorry.  You cannot read from this NetworkStream.");
            }
        }
    }
}