The Study And Implementation Of Online Examination System

Online examination systems contain all the process of question creating, paper creating, question answering and scoring by information technology in the network. At the same time, the capacity of questions and examinees is extended by database and network technology, and the efficiency of composing papers, scoring and querying is improved.But, restricted by the problems of online cheating and time synchronization, online examination system development meets a bottle neck. According to the difficulty to prevent online cheating and to realize time synchronization, there was not a effective solution in the past research.The object of this project is to implement a small but complete online examination system. This system includes 9 functions, such as question editing, question auditing, paper editing, paper auditing, examination planning, examination execution, paper scoring, score querying and management. Several question types are supported, including completion, simple choice, multiple choice, true or false, discussion, essay, and can be extended.This paper makes a detail analysis on solving how to prevent online cheating and to realize time synchronization. And then get a conclusion that the most effective and direct approach to prevent online cheating is to intercept the keyboard switch operations, because if a examinee atempt to cheat online, he must switch to leave the examination interface first. The mainstream B/S structure can not intercept all the keyboard switch operations. The C/S structure can intercept all the switch operations, but the system will meet the difficulty of deployment, data exchangement and system maintainance.Online examination time synchroniazation requires all the examination clients to begin or finish answering simultaneously and display the time synchronously. If a C/S structure applied, a lot of communication coding work should be done to synchronize time between server and clients. If a B/S structure applied, time synchroniazation can be realized, but the whole webpage refreshment must be avoided.According to the design, this project uses Microsoft Visual Studio 2005 as a tool of development, use Microsoft SQL Server 2005 as the database management system, implements question editing, question auditing, paper editing, paper auditing, examination planning, examination execution, paper scoring, score querying and management by ASP.Net technology. And sums up the data structure of completion, simple choice, multiple choice, true or false, discussion and essay. This project develops an online examination client by using Microsoft .Net framework, and realizes to prevent examinees from switching leaving the examination interface. This client program can run directly in any computer that has a .Net framework. So it is easy to deploy the system. And the online examination webpages can be suported and protected by the client. AJAX technology is applied in this system to implement the partial refreshment of the time display part on examination webpages, and examinees will not be disturbed by whole screen refreshment. Time synchronization is ensured because every client displays the same server time.As a common technology, the examination client of this system can also be used to help other B/S online examination system prevent online cheating, and has its value in popularization.