Sending multiple Textmessages and Images via TcpClient

[Hasok]

Hey,

i'm trying to get into Sockets and im struggeling with sending multiple images.

Server:

public static void SendImage(int clientID)
{
TcpClient client = clientList[clientID];
NetworkStream nwStream = client.GetStream();

//---write back the text to the client---
byte[] bytesToSend2 = ASCIIEncoding.ASCII.GetBytes("Sending Image");
Console.WriteLine("Sending Image Message");
nwStream.Write(bytesToSend2, 0, bytesToSend2.Length);


Bitmap img = new Bitmap("mainchar.jpg");
byte[] bytesToSend = ImageToByte(img);
nwStream.Write(bytesToSend, 0, bytesToSend.Length);
nwStream.Dispose();
Console.WriteLine("Image sent");

}

public static void SendMessage(int clientID,String message)
{
TcpClient client = clientList[clientID];
NetworkStream nwStream = client.GetStream();

byte[] bytesToSend2 = ASCIIEncoding.ASCII.GetBytes("Sending Text " + message);
Console.WriteLine("Sending Image Message " + message);
nwStream.Write(bytesToSend2, 0, bytesToSend2.Length);
}

Client:

class Program
{
const int PORT_NO = 8081;
const string SERVER_IP = "127.0.0.1";
static void Main(string[] args)
{
Console.WriteLine("Enter id:");
String ergebnis = Console.ReadLine();

//---create a TCPClient object at the IP and port no.---
TcpClient client = new TcpClient(SERVER_IP, PORT_NO);
NetworkStream nwStream = client.GetStream();

byte[] bytesToSend = ASCIIEncoding.ASCII.GetBytes(ergebnis);

//---send the text---
Console.WriteLine("Sending : " + ergebnis);
nwStream.Write(bytesToSend, 0, bytesToSend.Length);

//---read back the text---

byte[] bytesToRead = new byte[client.ReceiveBufferSize];

while (true)
{
if (nwStream.DataAvailable)
{

int bytesRead = nwStream.Read(bytesToRead, 0, client.ReceiveBufferSize);
Console.WriteLine("Received : " + Encoding.ASCII.GetString(bytesToRead, 0, bytesRead));

if (Encoding.ASCII.GetString(bytesToRead, 0, bytesRead).Contains("Image"))
{
Console.WriteLine();
Image img = Image.FromStream(nwStream);
img.Save($"newimage.png", ImageFormat.Png);
}
}
}

}


Sending a textmessage multiple times is no problem at all but the sending of an Image only works once.

Once i send the image textmessaging is not possible anymore either and the line

NetworkStream nwStream = client.GetStream();


is throwing a InvalidOperationException. I ran out of ideas how to fix this.


Thanks in advance

Jan

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