Design And Implementation Of Web-based Examination System

Office automation has already become an important way that to improve work efficiency and to save resources in any kind of business. The office automation goes far ahead in the examination system of the education industry.The examination system has been developed from stand-alone version to network version. Although the network version of the examination system has made up for the lack of a stand-alone, the network version of the current system is mostly based on B/S or C/S two-tier structure. Although entirely based on Internet/Intranet platform, C/S structure features are that applications are usually distributed both in the client and server ends and when a client requests data resources visit, the server will return the results to the client. There are many structural problems in C /S system, such as: when the number of clients goes up rapidly, server performance will be greatly attenuated because of overloading. Once the application requirements change, the application programs need improving and it makes great inconvenience to the application maintenance and upgrade; a large amount of data transmission will make network load increased, and so on. Although B/S structure in these aspects had been improved, it is not good to be maintained, reused and saved because of the two-tier structure. So I developed NES, which is a three-tier structure and it is based on B/S.I chose Microsoft .NET Framework SDK v2.0 as a development tool and C# as a program language based on .NET platform to develop NES.I chose SQL Server 2000 to create the database and ADO.NET as database access technology.ASP.NET is only a part of .NET. Besides its carrying out compiling and translation quickly, the biggest merit of it is the way to separate paging from coding, In addition, .NET provides a variety of Web controls, to compare with the previous homepage written by ASP, it can be said a revolution. As distributed object technology gradually matured, once the multi-tier distributed system changes, it will eventually solve existing problem of the C/S structure. In multi-tier distributed applications, by adding another layer between the client and server, developers can set up a middle layer with business logic to separate the application business logic and user interface. Without changing client function, its users can provide a clear interface. If necessary, the middle layer can be amended to adapt to the application, avoiding mending thousands of client applications. So that developers can focus on analyzing, designing and developing the core business logic application to simply the application system and, to develop it, to update and upgrade it.ASP.NET can use rapid and convenient three-tier structure of .NET platform. The revolutionary change is that its homepage based on event processing, can be designated code for the background source document. .NET components can assemble components conveniently, background code can use the components which defined by itself through the control. By setting presentation on the Web, realizing business logic layers with components to achieve the three-tier structure easily.NES design takes the mission of vocational education into full consideration, that is "capacity-based, services-aimed and employment-oriented." There are only two types of test, the single item choice and multiple choices in the system. All the items included in the test are aimed to train students'skills and to store the knowledge which will be used in future.The system is divided into two independent parts as following:1. Foreground: student registration, searching passwords, examination selecting, online examination and exam results enquiry.2. Background: security testing, administrator management, student management, major management, courses management, tests and scores management. This article takes the system development as a background and introduces the design and the realization of the NES system, including all stages of SDLC (Software Development Life Cycle); feasibility analysis, requirements analysis, systems design (outline design and detailed design), coding, testing, deployment and maintenance. Meanwhile, the key technology and security design of this system have been stated too.