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Sending and receiving an image over sockets with C# | Screen Sharing Using C#

I am trying to set up two programs in C#. Basically, a simple server side set up where I want the client to listen for an image from the Server. Then, upon receiving the image, will display it in a PictureBox.
**I keep running into the following error:
A first chance exception of type 'System.ArgumentException' occurred in System.Drawing.dll or Parameter is not Valid**
SERVER SIDE
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace ServerComputer
{
public partial class mainForm : Form
{
public mainForm()
{
InitializeComponent();
}
Socket sendsocket;
private void goLive_Click(object sender, EventArgs e)
{
try
{
sendsocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
//The instantiation of socket, IP for 192.168.1.106, 10001 for Port
IPEndPoint ipendpiont = new IPEndPoint(IPAddress.Parse(ipAddress.Text.Trim()), 10001);
sendsocket.Connect(ipendpiont);
//Establishment of end point
Thread th = new Thread(new ThreadStart(threadimage));
th.IsBackground = true;
th.Start();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
return;
}
this.Hide(); //Hidden form
}
private Bitmap GetScreen()
{
Bitmap bitmap = new Bitmap(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height);
Graphics g = Graphics.FromImage(bitmap);
g.CopyFromScreen(0, 0, 0, 0, bitmap.Size);
return bitmap;
}
private void threadimage()
{
try
{
while (true)
{
MemoryStream ms = new MemoryStream();
GetScreen().Save(ms, System.Drawing.Imaging.ImageFormat.Bmp); //Here I use the BMP format
byte[] b = ms.ToArray();
sendsocket.Send(b);
Thread.Sleep(67); //I'm here to set to send a second
}
}
catch (Exception ee)
{
MessageBox.Show(ee.Message);
return;
}
}
}
}
CLIENT SIDE
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Sockets;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace ClientComputer
{
public partial class mainForm : Form
{
public mainForm()
{
InitializeComponent();
}
Socket hostSocket;
Thread thread;
string localIP = string.Empty;
string computrHostName = string.Empty;
private void mainForm_Load(object sender, EventArgs e)
{
computrHostName = Dns.GetHostName();
IPHostEntry hostname = Dns.GetHostEntry(Dns.GetHostName());
foreach (IPAddress ip in hostname.AddressList)
{
if (ip.AddressFamily.ToString() == "InterNetwork")
{
localIP = ip.ToString();
}
}
}
private void liveScreen_Click(object sender, EventArgs e)
{
Socket receiveSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint hostIpEndPoint = new IPEndPoint(IPAddress.Parse(localIP), 10001);
//Connection node
receiveSocket.Bind(hostIpEndPoint);
receiveSocket.Listen(10);
MessageBox.Show("start");
hostSocket = receiveSocket.Accept();
thread = new Thread(trreadimage);
thread.Start();
thread.IsBackground = true;
}
private void trreadimage()
{
int dataSize, i = 0;
try
{
while (true)
{
i++;
byte[] b = new byte[1024 * 1024 * 20]; //Picture of great
dataSize = hostSocket.Receive(b,0,b.Length,SocketFlags.None);
MemoryStream ms = new MemoryStream(b,0,dataSize,true);
//bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
Image img = Image.FromStream(ms);
img.Save("Image"+i+".Jpeg", System.Drawing.Imaging.ImageFormat.Jpeg);
videoBox.Image = img;
Console.WriteLine("Image Size: " + dataSize);
}
}
catch (Exception ee)
{
MessageBox.Show(ee.Message);
thread.Abort();
}
}
}
}

I can't stop repeating: never ever send raw data to a socket and expect to receive them the same way on another end. Use a protocol instead, to describe your network activity. In simplest case, send DWORD first that designated total length of your image. Same time, it's worth to reuse existing protocols like HTTP or what can fit your needs.
Why to bother? Well, if your "network" is just a piece of wire with two jacks on ends that placed directly into network cards of your PCs, that maybe happen to work OK (and still no 100% warranty). In real case, your "network connection" is a pack of inter-connections between routers, firewalls, switches and all that sort of hidden machinery in-between. They can (and will!) re-shape your stream the way they find useful for them. So, on the other end, how can your counterparty understand: is there everything received? how many packets to expect? etc. etc. etc.
So, sending some business data directly to socket is the same efficient as yelling to the window if you plan to say something to your friend living nearby. And, usually we use a phone with that kind of communication protocol "hey, Peter?.. yes, it's me.. listen, take care about your car as hail shower is coming... Bye!". See the difference?

Following code is working now, and I have few suggestions,
Try Async methods/events to receive and send data through socket instead of using loop or recursive methods.
Server Code.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Runtime.Serialization.Formatters.Binary;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace ServerComputer
{
publicpartialclassmainForm : Form
{
public mainForm()
{
InitializeComponent();
}
Socket sendsocket;
privatevoid goLive_Click(object sender, EventArgs e)
{
try
{
sendsocket = newSocket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
//The instantiation of socket, IP for 192.168.1.106, 10001 for PortIPEndPoint ipendpiont = newIPEndPoint(IPAddress.Parse(ipAddress.Text.Trim()), 10001);
sendsocket.Connect(ipendpiont);
//Establishment of end pointThread th = newThread(newThreadStart(threadimage));
th.IsBackground = true;
th.Start();
}
catch (Exception ee)
{
MessageBox.Show(ee.Message);
return;
}
this.Hide(); //Hidden form
}
privateBitmap GetScreen()
{
Bitmap bitmap = newBitmap(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height);
Graphics g = Graphics.FromImage(bitmap);
g.CopyFromScreen(0, 0, 0, 0, bitmap.Size);
return bitmap;
}
privatevoid threadimage()
{
try
{
MemoryStream ms = newMemoryStream();
GetScreen().Save(ms, System.Drawing.Imaging.ImageFormat.Bmp); //Here I use the BMP formatbyte[] b = ms.ToArray();
sendsocket.Send(b);
ms.Close();
}
catch (Exception ee)
{
// MessageBox.Show(ee.Message);//return;
}
Thread.Sleep(1000);
threadimage();
}
}
}
Clint Code.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace ClientComputer
{
public partial class mainForm : Form
{
public mainForm()
{
InitializeComponent();
}
Socket hostSocket;
Thread thread;
string localIP = string.Empty;
string computrHostName = string.Empty;
private void mainForm_Load(object sender, EventArgs e)
{
computrHostName = Dns.GetHostName();
IPHostEntry hostname = Dns.GetHostEntry(Dns.GetHostName());
foreach (IPAddress ip in hostname.AddressList)
{
if (ip.AddressFamily.ToString() == "InterNetwork")
{
localIP = ip.ToString();
}
}
this.Text = this.Text + " | " + localIP;
}
private void liveScreen_Click(object sender, EventArgs e)
{
connectSocket();
}
private void connectSocket()
{
Socket receiveSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint hostIpEndPoint = new IPEndPoint(IPAddress.Parse(localIP), 10001);
//Connection node
receiveSocket.Bind(hostIpEndPoint);
receiveSocket.Listen(10);
MessageBox.Show("start");
hostSocket = receiveSocket.Accept();
thread = new Thread(new ThreadStart(trreadimage));
thread.IsBackground = true;
thread.Start();
}
private void trreadimage()
{
int dataSize;
string imageName = "Image-" + System.DateTime.Now.Ticks + ".JPG";
try
{
dataSize = 0;
byte[] b = new byte[1024 * 10000]; //Picture of great
dataSize = hostSocket.Receive(b);
if (dataSize > 0)
{
MemoryStream ms = new MemoryStream(b);
Image img = Image.FromStream(ms);
img.Save(imageName, System.Drawing.Imaging.ImageFormat.Jpeg);
videoBox.Image = img;
ms.Close();
}
}
catch (Exception ee)
{
//MessageBox.Show(ee.Message);
//thread.Abort();
}
System.Threading.Thread.Sleep(1500);
trreadimage();
}
}
}

MemoryStream ms = new MemoryStream(b);
Image img = Image.FromStream(ms);
img.Save(imageName, System.Drawing.Imaging.ImageFormat.Jpeg);
videoBox.Image = img;
The error may due to corrupted or incomplete bmp image received in the MemoryStream it worked fine for me after increasing the socket send/receive buffers values
so adjust the sender "Socket.SendBufferSize" and the receiver "Socket.ReceiveBufferSize" to large values for example SendBufferSize = 1024 * 1024 * 20
this will help sending the entire image at once.
or another solution is to check whether the received data size (b.length) is the same as the sent image data size, before the code line of forming the received image stream

Crypted file is not working

I started to learn about cryptography and I wanted to make my own file crypter.
After you run the program you must select file to encrypt and then stub. For now it is now encrypting but it is binding two files. After selecting this two files it will create file first.exe. Splitter string is for program to know where stub code ends and when original file code starts. It is made like this
stub
splitter (some string)
original file
When you run first.exe then it will create file cos.exe which should be the original file. But when i run it, it doesnt work. It shows "This app is not going to work on your computer" and it says that i need to find version for my OS.
Here is the code for crypter:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
string stubpath, filepath;
private void Form1_Load(object sender, EventArgs e)
{
if (openFileDialog1.ShowDialog(this) == DialogResult.OK)
{
filepath = openFileDialog1.InitialDirectory + openFileDialog1.FileName;
}
if (openFileDialog1.ShowDialog(this) == DialogResult.OK)
{
stubpath = openFileDialog1.InitialDirectory + openFileDialog1.FileName;
}
byte[] originalfile = File.ReadAllBytes(filepath);
byte[] array = Encoding.ASCII.GetBytes("password");
byte[] originalstubfile = File.ReadAllBytes(stubpath);
byte[] arr1 = Combine(array, originalfile);
ByteArrayToFile("first.exe", Combine(originalstubfile,arr1));
}
public bool ByteArrayToFile(string fileName, byte[] byteArray)
{
try
{
using (var fs = new FileStream(fileName, FileMode.Create, FileAccess.Write))
{
fs.Write(byteArray, 0, byteArray.Length);
return true;
}
}
catch (Exception ex)
{
return false;
}
}
public static byte[] Combine(byte[] first, byte[] second)
{
byte[] ret = new byte[first.Length + second.Length];
Buffer.BlockCopy(first, 0, ret, 0, first.Length);
Buffer.BlockCopy(second, 0, ret, first.Length, second.Length);
return ret;
}
}
}
And here is the code for stub:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApplication3
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
string exePath = Application.ExecutablePath;
byte[] originalfile = File.ReadAllBytes(exePath);
var str = System.Text.Encoding.Default.GetString(originalfile);
string[] tokens = str.Split(new[] { "password" }, StringSplitOptions.None);
//0 stub
//1 original file
byte[] toBytes = Encoding.ASCII.GetBytes(tokens[1]);
File.WriteAllBytes(System.AppDomain.CurrentDomain.BaseDirectory+ "cos.exe", toBytes);
}
}
}
EDIT:
Here is the error(Polish Language)
Also I found that when I delete splitter string and I dont use stub but I use 2 files like ex. putty.exe then it works, so I think that there is a problem in the stub.

Writing/reading string through NetworkStream (sockets) for a chat

Sorry if this is hard to understand, trying out C# for the first time.
I am trying to make a simple public 'chat' between clients that are connected to the server. I've tried passing integers to the server and printing them out and everything was fine, however,when I switched to strings, it seems that it can only pass 1 character (because of ns.Write(converted, 0, 1);). If I increase the ns.Write to ns.Write(converted,0,10) everything crashes (both the client and the server) when I enter a message that is less than 10 characters.
Server code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Net.Sockets;
namespace MultiServeris
{
class Multiserveris
{
static void Main(string[] args)
{
TcpListener ServerSocket = new TcpListener(1000);
ServerSocket.Start();
Console.WriteLine("Server started");
while (true)
{
TcpClient clientSocket = ServerSocket.AcceptTcpClient();
handleClient client = new handleClient();
client.startClient(clientSocket);
}
}
}
public class handleClient
{
TcpClient clientSocket;
public void startClient(TcpClient inClientSocket)
{
this.clientSocket = inClientSocket;
Thread ctThread = new Thread(Chat);
ctThread.Start();
}
private void Chat()
{
byte[] buffer = new byte[10];
while (true)
{
NetworkStream ns = clientSocket.GetStream();
ns.Read(buffer,0,1);
string line = Encoding.UTF8.GetString(buffer);
Console.WriteLine(line);
}
}
}
}
Client code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net.Sockets;
namespace Klientas
{
class Klientas
{
static void Main(string[] args)
{
while (true)
{
TcpClient clientSocket = new TcpClient("localhost", 1000);
NetworkStream ns = clientSocket.GetStream();
byte[] buffer = new byte[10];
string str = Console.ReadLine();
byte[] converted = System.Text.Encoding.UTF8.GetBytes(str);
ns.Write(converted, 0, 1);
}
}
}
}

You're best using the BinaryReader/BinaryWriter classes to correctly format and read out data. This removes the need to process it yourself. For example in the client do:
BinaryWriter writer = new BinaryWriter(clientSocket.GetStream());
writer.Write(str);
And in the server:
BinaryReader reader = new BinaryReader(clientSocket.GetStream());
Console.WriteLine(reader.ReadString());

When using BinaryReader or BinaryWriter on the same stream, and you have .NET framework version 4.5 or above, be sure to leave the underlying stream open by using the overload:
using (var w = new BinaryWriter(stream, Encoding.UTF8, true)) {}

Deadlock with MemoryMappedFile streaming

I have a small problem performing MemoryMappedFile streaming.
I have 2 projects, one for sending bytes and another for reading bytes. Between these two processes should be a 2 second sleep timer.
I've implemented all of this, but when the software attempts to do the read it appears to encounter a deadlock. The code for both processes is below.
Can anyone help me find the issue?
namespace ProcesComunication
{
class Program
{
static void Main(string[] args)
{
MemoryMappedFile mmf = MemoryMappedFile.CreateNew("AAB", 1024);
MemoryMappedViewStream mStream = mmf.CreateViewStream();
BinaryWriter bw = new BinaryWriter(mStream);
Mutex mx = new Mutex(true, "sync");
while (true)
{
Thread.Sleep(2000);
Console.WriteLine("TEST");
bw.Write(DateTime.Now.ToString());
mx.ReleaseMutex();
}
bw.Close();
mStream.Close();
}
}
}
namespace ProcesRead
{
class Program
{
static void Main(string[] args)
{
MemoryMappedFile mmf = MemoryMappedFile.OpenExisting("AAB");
MemoryMappedViewStream mStream = mmf.CreateViewStream();
BinaryReader br = new BinaryReader(mStream);
Mutex mx = Mutex.OpenExisting("sync");
while (true)
{
mx.WaitOne();
Console.Write(br.ReadString());
mx.ReleaseMutex();
}
br.Close();
mStream.Close();
}
}
}

I tried and found simple solution, below is a code:
Thanks to all contributors for answers.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Threading;
using System.IO.MemoryMappedFiles;
namespace ProcesComunication
{
class Program
{
static void Main(string[] args)
{
MemoryMappedFile mmf = MemoryMappedFile.CreateNew("AAB", 1024);
MemoryMappedViewStream mStream = mmf.CreateViewStream();
BinaryWriter bw = new BinaryWriter(mStream);
Mutex mx = new Mutex(true, "sync");
while (true)
{
mx.WaitOne();
Thread.Sleep(2000);
var random = new Random();
var nextValue = random.Next().ToString();
Console.WriteLine(nextValue);
bw.Write(nextValue);
mx.ReleaseMutex();
}
bw.Close();
mStream.Close();
}
}
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Threading;
using System.IO.MemoryMappedFiles;
namespace ProcesRead
{
class Program
{
static void Main(string[] args)
{
MemoryMappedFile mmf = MemoryMappedFile.OpenExisting("AAB");
MemoryMappedViewStream mStream = mmf.CreateViewStream();
BinaryReader br = new BinaryReader(mStream);
Mutex emx = Mutex.OpenExisting("sync");
while (true)
{
Console.WriteLine(br.ReadString());
emx.WaitOne(2000);
}
br.Close();
mStream.Close();
}
}
}

There is no need to use a synchronization object (Mutex). MemoryMappedFile is thread safety between the processes. Don't use mutex. And control reader to it have data for reading.

using sockets to chat in web app gives me an error

I Tried to use sockets in asp.net using C#.
The commented line in the client code gives me error.
The server code is running properly.
This is the Client Code which Gives error.
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Threading;
using System.Net;
using System.Net.Sockets;
using System.Text;
public partial class _Default : System.Web.UI.Page
{
System.Net.Sockets.TcpClient clientSocket = new System.Net.Sockets.TcpClient();
NetworkStream serverStream = default(NetworkStream);
string readData = null;
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Post_Click(object sender, EventArgs e)
{
if (txtmsg.Text != "")
{
byte[] outStream = System.Text.Encoding.ASCII.GetBytes(txtmsg.Text + "$");
serverStream.Write(outStream, 0, outStream.Length);
// This line gives error Saying Object reference not set to an instance of an object.
serverStream.Flush();
}
}
protected void Connect_Click(object sender, EventArgs e)
{
if (txtSub.Text != "")
{
try
{
readData = "Conected to Chat Server ...";
msg();
clientSocket.Connect("127.0.0.1", 8888);
serverStream = clientSocket.GetStream();
byte[] outStream = System.Text.Encoding.ASCII.GetBytes(txtSub.Text + "$");
serverStream.Write(outStream, 0, outStream.Length);
serverStream.Flush();
Thread ctThread = new Thread(getMessage);
ctThread.Start();
}
catch
{
//Disconnect();
}
}
}
private void getMessage()
{
while (true)
{
serverStream = clientSocket.GetStream();
int buffSize = 0;
byte[] inStream = new byte[10025];
buffSize = clientSocket.ReceiveBufferSize;
serverStream.Read(inStream, 0, buffSize);
string returndata = System.Text.Encoding.ASCII.GetString(inStream);
readData = "" + returndata;
msg();
}
}
private void msg()
{
//if (this.InvokeRequired)
// this.Invoke(new MethodInvoker(msg));
//else
txtget.Text = txtget.Text + Environment.NewLine + " >> " + readData;
}
}

Your serverSteam object isn't being properly initialised and therefore causes an object error when you try to reference it.
You need to create a new NetworkSteam with a Socket object, and ensure that your Socket object is connected:
Socket my_socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
..
// connect socket and any other operations
..
NetworkStream my_network_stream = new NetworkStream(my_socket);