摘 要即时通讯(Instant Messaging)是目前Internet上最为流行的通讯方式，而各种各样的即时通讯软件也层出不穷；服务提供商也提供了越来越丰富的通讯服务功能。随着互联网的进展，即时通讯的运用将日益广泛。本文围绕即时通讯的基本文字沟通功能，设计了管理在线用户，维护在线用户，实现文字通信的功能。本系统使用TCP和UDP协议作为传输层的协议，更加便捷了用户之间的通讯和交友。 该系统为用户提供了一个集文字通信、在线信息、文件传输于一体的即时通信平台。经过几个月的项目开发、测试，本即时通讯系统现已可以正常运行。关键词：TCP/IP，C/S，Winsock，即时通信系统，Visual Basic ABSTRACTInstant Messaging is currently the most popular way to communicate on the Internet ， by the way various Instant Messaging software have been continuously appearing; Service provider offers more and more communication services nowadays. As the development of the Internet, Instant Messaging will perform a wider use and is growing up day after day. This thesis is based on the function of exchange, which is the basic character of instant messaging system, online users management, safeguarding online users and exchange message are come true. This system has offered an instant messaging platform incorporating characters communication, online information and file transfer. Through several months develop and test cycle, this instant messaging system can already used to run now.Keywords: TCP/IP, C/S, Winsock, Instant Messenger System, Visual Basic 目录摘要....................................................................................................................................IABSTRACT.....................................................................................................................II第 1 章 绪论......................................................................................................................11.1 讨论背景及意义...........................................
