Com +-based Components In The Development Of Management Information Systems

Nowadays, Management Information System (MIS) is widely used in many fields with the development of computer application techniques and theories, and it has become a very important part of electronic information construction. But with the update of system, the scale" of software and complexity are increasing, thus, it's hard to develop, debug or update the old system. Traditional method of software development is long-period and low efficiency, and it's not appropriate for describing more complicated systems any more. The development and application of MIS is restricted because of this fact. It is to resolve this problem that people explore and develop component techniques, which are based on Object-Oriented and could increase the efficiency of software development, decrease repeated working, and enhance robustness of systems. This paper studies the theory and application of component techniques, further more, the prototype of general components, which are based on COM+ component technique and could be used in MIS field, is produced according to the study.Component software development method has come into being for only a few years, and there is no uniform criterion by now. In MIS field, only a few systems use this method, and the practicability, functionality, expansibility and independency of components, which are used in MIS, are not gratifying. In this paper, the prototype of general components makes some improvements aiming at the disadvantages above. Meanwhile, this paper introduces the process of analysis, design, modeling and implementation of general components, as well as it shows how to use general components during the course of MIS development. This paper also studies the application of ActiveX control technique, Microsoft Message Queue technique and Publishing/Subscripting Event system in the development of the prototype.This paper explores the application of component technique, and produces the prototype of general component, which refers to the common data process (add, delete, modify and query), report forms and the process of MIS development. In this paper, general functions of MIS are analyzed firstly, using traditional method, and are layered from the viewpoint of Three-Tiers Model. Then, special objects are abstracted from each layer. Also some objects are added for component's disadvantages above, and object models are created accordingly. Then interrelated objects are encapsulated into different components. The prototype of general components, are implemented in the environment of Windows 2000 and Visual Basic 6.0. At last, this paper summarizes the method of component development.In order to make general components be generally used in MIS field, the concept of BasicTable and Alias are imported into the design process. The prototype of general components makes it possible that different MIS could share some data. Miscellaneous operations are encapsulated into one control based on the comprehensive specialities of ActiveX control. Also, distributed working ability is implemented in general components.A serial of tests show that, the prototype of general components, which integrates some database operations, could lighten working intension of developers, and supports RAD (Rapid Application Development) of MIS as well. The reusability, functionality, practicability, expansibility and compact user interface of prototype are enhanced, too. On the whole, general components achieve previous design aim.