毕业论文外文翻译-VB的数据库编程分析

ANALYSIS OF DATABASE PROGRAMMING IN VB

VB (Visual Basic) is a visualization programming environment that Microsoft Corporation promotes based on the Basic language.It is simple and easy to study.It has formidable function so that many computer amateurs really like it.A lot of application softwares all use VB as the software development platform.When we use VB to develop the application software,how to use the database and carry on the management of the database is concerned by all exploiters.VB has provided many tools and methods for database programming.What method is used to visit the database depends on users’different demands,a simple analysis of the VB database programming is explained as followings.

1.DAO Technology

By using Microsoft company’s Jet Database Engine (Jet database engine),DAO (Data Access Object) the technology mainly provides visit to ISAM (smooth index search method) type database,such as the realization of the visit to database like FoxPro,Access, Dbase.

1.1 Use Data Controls

Data controls are produced by using “Data” button in the toolbox.It has 3 basic attributes:Connect,Database Name and RecordSource.Connect attribute specifys the database type that data controls visit,the default database is the Access database.The value of the Database Name attribute is the database filename which contains the complete path.The Record Source attribute is the recordset that we visit,also can be tables or SQL sentences.If we will visit table stud of database file teacher mdb of TEMP folder under D plate,then Data controls’s Connect attribute is null,and the Database Name attribute is “D: \temp \ teacher mdb”,the value of the Record Source attribute is “stud”.This can accomplish the binding between Data controls and database records. Through the methods of Data controls like Add new,Update,Delete, Move last,we can visit the database as every request.When we browse the content in database,Data controlls is used frequently with DBGrid,it provides data inquiry in grid way.

1.2 Use DAO Object Storehouse

The model of the DAO object storehouse is mainly using hierarchical structure, Dentine is the object in the topmost story,below it are two object sets,Errors and workspace, under the workspace object,is the Databases set.When the application procedure quotes the DAO object storehouse,it produces only a Dentine object,and produces a default automatical working space object named workspace.When not mentioned,all database operations are all work in workspace(0),which is a default work area.But we must pay attention:The Jet engine will not starts automatically after VB has been loaded. Only when we choose References in the menu of Project can we select Microsoft DAO 3.5 Object Library to use.We create databases with the method “Create Database”in DAO,use