问题
I need to implement HTTP protocol through TCP. I already had a TCP/IP client-server program which had been working absolutely fine.
Now, I have done some minor change in the source code so that it behaves as an HTTP client-server. But, unfortunately it stopped working.
The following code ...
public void Write(string str)
{
if (IsConnected)
{
byte[] strBytes = Encoding.UTF8.GetBytes(str);
byte[] lenBytes = BitConverter.GetBytes(strBytes.Length);
Array.Reverse(lenBytes);
writer.Write(lenBytes);
writer.Write(strBytes);
writer.Flush();
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
public string Read()
{
if (IsConnected)
{
byte[] lenBytes = reader.ReadBytes(4);
Array.Reverse(lenBytes);
int len = BitConverter.ToInt32(lenBytes, 0);
byte[] bytes = reader.ReadBytes(len);
string str = Encoding.UTF8.GetString(bytes);
return str;
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
is changed to:
public void Write(string str)
{
if (IsConnected)
{
byte[] send = Encoding.ASCII.GetBytes(str);
writer.Write(send);
writer.Flush();
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
public string Read()
{
if (IsConnected)
{
StreamReader sr = new StreamReader(stream);
string str = sr.ReadToEnd();
return str;
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
What is the issue here?
Detailed Source Code
The following class is used by both server program and client program.
modified:
namespace MyClientServer
{
public class ClientClass
{
private string Host { get; set; }
private int Port { get; set; }
private bool IsConnected = false;
public string ID { get; private set; }
public TcpClient Tcp { get; private set; }
NetworkStream stream;
private StreamReader sr;
private StreamWriter writer;
public ClientClass()
{
Random rnd = new Random();
ID = AlphaNumRandom.GenerateUpperCaseString(5, rnd);
}
//constructor for server program.
public ClientClass(TcpListener listener)
{
Tcp = listener.AcceptTcpClient();
Host = ((IPEndPoint)Tcp.Client.RemoteEndPoint).Address.ToString();
Port = ((IPEndPoint)Tcp.Client.LocalEndPoint).Port;
IsConnected = true;
stream = Tcp.GetStream();
sr = new StreamReader(stream);
writer = new StreamWriter(stream);
ID = Read();
Console.WriteLine("Client [{0}] is now connected.", ID);
}
public bool Connect()
{
if (IsConnected == false)
{
Console.WriteLine("Client [{0}] is now connected.", ID);
IsConnected = true;
Tcp = new TcpClient(Host, Port);
stream = Tcp.GetStream();
sr = new StreamReader(stream);
writer = new StreamWriter(stream);
return true;
}
return false;
}
//constructor for client.
public ClientClass(string host, int port)
{
Random rnd = new Random();
ID = AlphaNumRandom.GenerateUpperCaseString(5, rnd);
Host = host;
Port = port;
}
public void Write(string str)
{
if (IsConnected)
{
byte[] send = Encoding.ASCII.GetBytes(str);
writer.Write(send);
writer.Flush();
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
public string Read()
{
if (IsConnected)
{
StreamReader sr = new StreamReader(stream);
string str = sr.ReadToEnd();
return str;
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
public void PrintID()
{
Console.WriteLine("Client ID = {0}", ID);
}
public void SendIdToServer()
{
this.Write(ID);
}
public bool Disconnect()
{
if (IsConnected)
{
if (Tcp != null)
{
Tcp.Close();
Tcp = null;
Console.WriteLine("\nClient [{0}] is now disconnected.", ID);
return true;
}
}
return false;
}
}
}
original:
namespace MyClientServer
{
public class ClientClass
{
private string Host { get; set; }
private int Port { get; set; }
private bool IsConnected = false;
public string ID { get; private set; }
public TcpClient Tcp { get; private set; }
private BinaryReader reader;
private BinaryWriter writer;
public ClientClass()
{
Random rnd = new Random();
ID = AlphaNumRandom.GenerateUpperCaseString(5, rnd);
}
//constructor for server program.
public ClientClass(TcpListener listener)
{
Tcp = listener.AcceptTcpClient();
Host = ((IPEndPoint)Tcp.Client.RemoteEndPoint).Address.ToString();
Port = ((IPEndPoint)Tcp.Client.LocalEndPoint).Port;
IsConnected = true;
NetworkStream stream = Tcp.GetStream();
reader = new BinaryReader(stream);
writer = new BinaryWriter(stream);
ID = Read();
Console.WriteLine("Client [{0}] is now connected.", ID);
}
public bool Connect()
{
if (IsConnected == false)
{
Console.WriteLine("Client [{0}] is now connected.", ID);
IsConnected = true;
Tcp = new TcpClient(Host, Port);
NetworkStream stream = Tcp.GetStream();
reader = new BinaryReader(stream);
writer = new BinaryWriter(stream);
return true;
}
return false;
}
//constructor for client.
public ClientClass(string host, int port)
{
Random rnd = new Random();
ID = AlphaNumRandom.GenerateUpperCaseString(5, rnd);
Host = host;
Port = port;
}
public void Write(string str)
{
if (IsConnected)
{
byte[] strBytes = Encoding.UTF8.GetBytes(str);
byte[] lenBytes = BitConverter.GetBytes(strBytes.Length);
Array.Reverse(lenBytes);
writer.Write(lenBytes);
writer.Write(strBytes);
writer.Flush();
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
public string Read()
{
if (IsConnected)
{
byte[] lenBytes = reader.ReadBytes(4);
Array.Reverse(lenBytes);
int len = BitConverter.ToInt32(lenBytes, 0);
byte[] bytes = reader.ReadBytes(len);
string str = Encoding.UTF8.GetString(bytes);
return str;
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
public void PrintID()
{
Console.WriteLine("Client ID = {0}", ID);
}
public void SendIdToServer()
{
this.Write(ID);
}
public bool Disconnect()
{
if (IsConnected)
{
if (Tcp != null)
{
Tcp.Close();
Tcp = null;
Console.WriteLine("\nClient [{0}] is now disconnected.", ID);
return true;
}
}
return false;
}
}
}
回答1:
I took the advice of @Jimi and also took a look at the source code from this link.
Now my source code looks like the following:
public string Read()
{
if (IsConnected)
{
byte[] buffer = new byte[Tcp.ReceiveBufferSize];//create a byte array
int bytesRead = stream.Read(buffer, 0, Tcp.ReceiveBufferSize);//read count
string str = Encoding.ASCII.GetString(buffer, 0, bytesRead);//convert to string
return str;
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
public void Write(string str)
{
if (IsConnected)
{
byte[] bytesToSend = ASCIIEncoding.ASCII.GetBytes(str);
stream.Write(bytesToSend, 0, bytesToSend.Length);
stream.Flush();
}
else
{
throw new Exception("Client " + ID + " is not connected!");
}
}
and, it is working fine.
来源：https://stackoverflow.com/questions/60467200/why-has-the-server-stopped-responding-after-a-change-in-source-code