Problem communicating with ENC28J60

Question

I want to send/receive strings to/from an ENC28J60 via a C# application. I used my own "protocol" to do this. For example I send "" to Arduino and it replies with a string containing temperature values. This method works fine in Serial communication mode, but freezes in Network mode. What am I missing here? Is there a better method to do this? I'm new to socket programming. I'm using UIPEthernet.h by ntruchsess.

My server-side (Arduino) code:

void checkAndReceiveFromTCPClients(){
 size_t size;
 if (EClient = EServer.available()){
 char* strIn;
 if(size = EClient.available() > 0){
 strIn = (char*)malloc(size + 1);
 memset(strIn, 0, size + 1);
 EClient.read(strIn, size);
 }
 strIn[size] = 0;
 String strInput = String(strIn);
 strInput.trim();
 //This replies to client (sends string) with a string (EClient.write(answer)):
 InterpretInputString(strInput); 
 //EClient.stop();
 EClient.flush();
 }
}

C# code:

string SendAndReceiveOverNet(string Command) {
 Byte[] data = System.Text.Encoding.ASCII.GetBytes(Command);
 NetworkStream stream = TClient.GetStream();
 stream.Write(data, 0, data.Length);
 data = new Byte[256];
 String responseData = String.Empty;
 Int32 bytes = stream.Read(data, 0, data.Length);
 responseData = System.Text.Encoding.ASCII.GetString(data, 0, bytes);
 return responseData;
}

Answer 1

Something like this is needed here. If you use stream.Read without TClient.Available, the program will freeze or crash.

C# code:

string SendAndReceiveOverNet(string Command) {
 Byte[] data = System.Text.Encoding.ASCII.GetBytes(Command);
 NetworkStream stream = TClient.GetStream();
 stream.Write(data, 0, data.Length);
 String responseData = String.Empty;
 Int32 size = TClient.Available;
 if (size > 0)
 {
 data = new Byte[size];
 Int32 bytes = stream.Read(data, 0, data.Length);
 responseData = System.Text.Encoding.ASCII.GetString(data, 0, bytes);
 }
 return responseData;
}