VB的相关中英文文献对照文档格式.docx

VB的相关中英文文献对照文档格式.docx

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ThroughMicrosoftJetDatabaseEngine（Jetdatabaseengine）,DAO（DataAccessObject）thetechnologymainlyprovidesvisittoISAM（smoothindexsearchmethod）typedatabase,likerealizationvisittodatabaseandsoonFoxPro,Access,Dbase.

1.1usesDatatocontrol

Datacontrolsareusesinthetoolbox“Data”thebuttontoproduce.Shouldcontroltohave3basicattributes:

Connect,DatabaseNameandRecordSource.Connectattributespecifieddatacontrolsthedatabasetypewhichmustvisit,thedefaultistheAccessdatabase;

TheDatabaseNameattributevalueforcontainsthecompletewaythedatabasefilename;

TheRecordSourceattributevaluefortherecordcompendiumwhichmustvisit,maybeshows,butalsoSQLsentence.IfvisitsunderDplateTEMPfolderteachermdbinthedatabasefiletablestud,thenDatacontrolstheConnectattributeforspatially,theDatabaseNameattributeis“D:

\temp\teachermdb”,theRecordSourceattributevalueis“stud”.LikethisrealizedDatatocontrolandbetweenthedatabaserecordingdatabinding,throughtransferredDatatocontrolmethodrealizationsandsoontheAddnew,Update,Delete,Movelastvisittothedatabaseeachkindofrequest,whencarriedonthedatabasecontentbrowsing,DatacontrolledalsofrequentlytocontrolthecoordinateusewithDegrade,providedthegridwaythedatainquiry.

1.2usestheDAOobjectstorehouse

TheDAOobjectstorehousemodelmainlyusesthehierarchicalstructure,Dentineisthetopmoststoryobject,belowhasErrorsandtheworkspacetwoobjectsets,undertheworkspaceobjectistheDatabasesset.QuotestheDAOobjectstorehousewhentheapplicationprocedure,onlycanproduceaDentineobject,andproducesadefaultautomaticallyworkingspaceobjectworkspace,inotherhasnotassignedinthesituation,alldatabaseoperationallisinworkspace（0）carriesoutinthedefaultworkarea,butmustpayattention:

TheJetenginestartsafterVBcannotloadautomatically,onlythenchoosesReferencesintheProjectmenuitem,thenselectsMicrosoftDAO3.5ObjectLibraryonlythentobepossibletouse.usestheCreateDatabasemethodfoundationdatabaseinDAO,withtheCreateTableDefmethodfoundationtable,opensthedatabasewiththeOpenDatabasemethodwhichassigns,openstherecordcompendiumwiththeOpenrecordsetmethod,usesAddnew,Update,Delete,Movefirst,Editmethodsandsoonrecordsetobjecttobepossibletorealizefortableeachkindofoperation.

ThroughtheDAOothermethodtransfer,mayrealizetothetableotheroperations.

1.RDOtechnology

RDOisprovidestorelatestheODBCdatapoolvisitconnection.WhenneedstovisitotherdatabaselikeSQLServer,Oracle,whenspeciallyneedstoestablishthecustomer/serverapplicationprocedure,mayusethelongrangedatatocontrolRDC（RemoteDataControl）andlongrangedataobjectRDO（RemoteDataControl）realizesthroughtheODBCdrivervisittothedatabase.

UsesODBCvisitswhensomedatabasemustfirstinstallthecorrespondingdriver,establishesadatapool,throughdatapoolvisitcorrespondingdatabasewhichassigns.EstablishestheODBCdatapoolisturnson“thecontrolpanel”thewindow,double-clickstheODBCexecutiveprogramtheicon,inopensintheODBCdatapoolsupervisordialogboxsingle-clicks“Add”thebuttontofoundthedatapool,andchoosescorrespondingdatabase.

2.1usesRDCtocontrol

ControlswithDATAtobeverysimilarintheuse,assignswiththeDatasourcenameattributetocontrolabindingthedatasourcename,assignstherecordcompendiumwiththeSQLattribute,differentis,controlsintheSQLattributeinRDCtohavetousetheSQLsentencetoassign.WhendatabasebrowsingalsofrequentlycontrolstheunionusewithDBGrid.

2.2usestheRDOobjectstorehouse

InusesinfrontoftheRDOobject,shouldchooseReferencesintheProjectmenuitem,afterselects“MicrosoftRemoteDataObject2.0”onlythentobepossibletouse.

usesRDOtovisittheODBCdatapoolthestepis:

（1）EstablishesaRDOenvironmentobject.

（2）UsestheOpenconnectionmethodtoopenanODBCdatapool.

（3）UsestheOpenResultsetmethodtoestablishtheresultcollectionobject.

（4）Useassignsthemethod,carriesoneachkindofoperationtotheresultcentralismrecording.

Afterfoundstheasthisresultcollectionobject,issimilarwiththeDAOobjectstorehouseuse,maythroughtransfermethodrealizationsandsoonitsAddnew,Update,Deletevisittoassignthedatapooleachkindofrequest.

3.ADOtechnology

ADO（ActiveXDataObjects）istheMicrosoftmostrecentdataaccessingtechnology,heusesgeneraldataaccessingconnectionUDA（UniversalDataAccess）,alldatastandardwillbeonekindofdatapool,passesthroughOLEtheDBconnectionfiltration,transformsonekindofgeneraldataformatbythesameway,enablestheapplicationproceduretovisitthiskindofdata.OLEDBisanunderlyingbeddataaccessingconnection,mayvisiteachkindofdatapoolwithhim,includingtraditionalrelationsdatabase,aswellaselectronicmailsystemandfromdefinitioncommercialobject.

3.1usesADOtocontrol

single-clickstheComponentsorderintheProjectmenu,selects“MicrosoftADODataControlintheComponentsdialogbox6.0（OLEDB）”,maycontrolADOtoincreasetocontrolsinabox.

controlstheConnectionstringattributethroughADOtoestablishthedatabasefilewhichOLEDBProviderandassigns,theRecordSourceattributeestablishesADOtocontroltheconnectedrecordsource.AresimilarwithDAOandRDO,controlsthroughADOwiththerecordingsourceconnection,mayrealizetoeachkindofdatabasefastaccess.

3.2usestheADOobjectstorehouse

Single-clickstheReferencesorderintheProjectmenu,selects“MicrosoftActiveXDataObjects2.0Library”intheReferencesdialogbox,mayincreaseintheprojecttotheADOobjectstorehousequotation.

Beforehandobjectmodel,likeDAOandRDOallarethelevel,lowdataobjectlikeRecordsetisseveralhighlevelobjectlikeEnvironmentandtheQueriedsub-object.ButADOisactuallydifferent,hehasdefinedagroupofplanetopobject,themostimportant3ADOobjectisConnection,RecordsetandCommand.

TheConnectionobjectusesinestablishingtheapplicationprocedureandthedatapoolconnection;

TheCommandobjectusesindefiningaSQLsentence,amemoryprocessorothercarriesontheoperationtothedatatheorder;

AftertheRecordsetobjectpreservationexecutionorderreturnsrecordcompendium.

ThroughtransferstheRecordsetobjectthealternativemeans,mayrealizetooperationsandsoonrecordcompendiumrevision,deletion,inquiry.

4conclusions

VBprovidedtheverymanymethodrealizationtothedatabaseoperation,inwhichDAOmainrealizationvisittoISAMdatabase,RDOhasprovidedtotheODBCdatapoolconnection,RDOandDAOallhasdevelopedforthequitematuretechnology,inVBinfrontof6.0isthemaindatabasevisittechnology,butActiveDataObjects（ADO）therecentgenerationofdatabaseinterfacewhichpromotesasMicrosoft,isdesignedwithrecentdataaccessinglevelOLEDBtheProvidertogetherjointoperation,providesthegeneraldataaccessing（UniversalDataAccess）,hehasprovidedverymanyadvantagetotheVBprogrammer,includingeasytouse,thefamiliarcontactsurface,thehighvelocityaswellasthelowmemorytakes（HasrealizedADO2.0Msado15.dlltoneedtotakethe342Kmemory,isslightlysmallerthanRDOMsrdo20.dll368K,probablyisDAO3.5Dao350.dlloccupiesthememory60%）,asaresultofabovereason,ADOgraduallywillreplaceotherdataaccessingconnection,willbecometheVBvisitdatabasethefundamentalmode.

VB的数据库编程方案分析

VB（VisualBasic）是微软公司推出的基于Basic语言的可视化编程环境,以其简单易学、功能强大而倍受广大电脑爱好者的青睐，许多应用软件都采用VB作为软件开发平台。

在用VB开发应用软件的过程中，如何使用数据库并对数据库进行管理是所有开发者关心的问题。

VB为数据库的编程提供了很多的工具和方式，究竟采用何种方式进行数据库的访问依赖于用的不同需求，以下就对VB的数据库编程方式做一个简单剖析。

1.DAO技术

通过Microsoft的JetDatabaseEngine（Jet数据库引擎），DAO（DataAccessObject）技术主要提供对ISAM（顺序索引查找方法）类型数据库的访问，如实现对FoxPro，Access，Dbase等数据库的访问。

1.1使用Data控件

Data控件是利用工具箱中的“Data”按钮产生的。

该控件有3个基本属性：

Connect，DatabaseName和RecordSource。

其中Connect属性确定数据控件要访问的数据库类型，默认为Access数据库；

DatabaseName属性的值为包含完整路径的数据库文件名；

RecordSource属性值为要访问的记录集，可以是表，也可是SQL语句。

如访问D盘TEMP文件夹下的teachermdb数据库文件中的表stud，则Data控件的Connect属性为空，DatabaseName属性为“D:

＼temp＼teachermdb”，RecordSource属性值为“stud”。

这样就实现了Data控件和数据库记录之间的数据绑定，通过调用Data控件的Addnew，Update，Delete，Movelast等方法实现对数据库的各种访问要求，在进行数据库内容浏览时，Data控件还经常和DBGrid控件配合使用，提供网格方式的数据查询。

1.2利用DAO对象库

DAO对象库的模型主要采用层次结构，Dentine是最高层的对象，下面有Errors和workspace两个对象集合，在workspace对象下是Databases集合。

在应用程序引用DAO对象库时，只会产生一个Dbengine对象，并自动生成一个默认的工作空间对象workspace，在没有另外指定的情况下，所有的数据库操作都是在默认工作区workspace（0）中执行的，但要注意：

Jet引擎在VB启动后不会自动装入，只有在Project菜单项中选择References，然后选中Microsoft 

DAO3.5ObjectLibrary才可以使用。

在DAO中使用CreateDatabase方法创建数据库，用CreateTable方法创建表，用OpenDatabase方法打开指定的数据库，用Openrecordset方法打开记录集，使用recordset对象的Addnew，Update，Delete，Movefirst，Edit等方法可实现对表的各种操作。

通过DAO其他的方法调用，可实现对表的其他操作。

2.RDO技术

RDO是提供对关系型ODBC数