说明：   该程序是一个简单的聊天程序，主要功能是可以实现在两个不同电脑上进行聊天，不论是局域网还是互联网都可以。该程序是根据一个控制台程序修改而来，该控制台程序有两个类，服务器类和客户端类。
(The program is a simple chat program, the main function can be achieved in two different computers to chat, either LAN or the Internet can be. The program is based on a procedure adapted from the console, the console program has two classes, server classes and client classes.)