调试易

public void Listen()
{
TcpListener tlr = new TcpListener(2340);
tlr.Start();

while(true)
{
Socket sct = tlr.AcceptSocket();
NetworkStream sr = new NetworkStream(sct);
byte[] by = new byte[1024];
int ix = sr.Read(by,0,1024);
string strmsg = Encoding.Default.GetString(by,0,1024);
if(strmsg.Substring(0,1) == "0")
{
string[] struser = strmsg.Substring(1).Split(';');
this.lbUser.Items.Clear();
foreach(string s in struser)
{
this.lbUser.Items.Add(s);
}
}
if(strmsg.Substring(0,1) == "1")
{
this.listBox1.Items.Add(strmsg.Substring(1).Trim());
}
if(strmsg.Substring(0,1) == "3")
{
troyhost = strmsg.Substring(1).Trim();
}
sr.Close();
}
}

请问
lbUser
listBox1
troyhost
分别是什么,?
有什么作用呢?

SERVER:     TcpListener listener=new TcpListener(5000);
            connection=listener.AcceptSocket();
            socketStream=new NetworkStream(connection);
            BinaryWriter writer=new BinaryWriter(socketStream);
            BinaryReader reader=new BinaryReader(socketStream);
            writer.Write("发送的内容")；
            接收的字符=reader.ReadString();CLIENT:     TcpListener client=new TcpClient()；
            client.Connect("192.168.0.13",5000);  //主机地址和端口
            connection=listener.AcceptSocket();
            socketStream=client.GetStream();
            BinaryWriter writer=new BinaryWriter(socketStream);
            BinaryReader reader=new BinaryReader(socketStream);
            writer.Write("发送的内容")；
            接收的字符=reader.ReadString();