微软内部.net培训资料ado_net部分 (using ado_net to access data)

CONTENTSOVERVIEW1OVERVIEWOFADONET2CONNECTINGTOADATASOURCE10ACCESSINGDATAWITHDATASETS12USINGSTOREDPROCEDURES28LAB3USINGADONETTOACCESSDATA37ACCESSINGDATAWITHDATAREADERS46BINDINGTOXMLDATA53REVIEW59MODULE3USINGADONETTOACCESSDATAINFORMATIONINTHISDOCUMENTISSUBJECTTOCHANGEWITHOUTNOTICETHENAMESOFCOMPANIES,PRODUCTS,PEOPLE,CHARACTERS,AND/ORDATAMENTIONEDHEREINAREFICTITIOUSANDAREINNOWAYINTENDEDTOREPRESENTANYREALINDIVIDUAL,COMPANY,PRODUCT,OREVENT,UNLESSOTHERWISENOTEDCOMPLYINGWITHALLAPPLICABLECOPYRIGHTLAWSISTHERESPONSIBILITYOFTHEUSERNOPARTOFTHISDOCUMENTMAYBEREPRODUCEDORTRANSMITTEDINANYFORMORBYANYMEANS,ELECTRONICORMECHANICAL,FORANYPURPOSE,WITHOUTTHEEXPRESSWRITTENPERMISSIONOFMICROSOFTCORPORATIONIF,HOWEVER,YOURONLYMEANSOFACCESSISELECTRONIC,PERMISSIONTOPRINTONECOPYISHEREBYGRANTEDMICROSOFTMAYHAVEPATENTS,PATENTAPPLICATIONS,TRADEMARKS,COPYRIGHTS,OROTHERINTELLECTUALPROPERTYRIGHTSCOVERINGSUBJECTMATTERINTHISDOCUMENTEXCEPTASEXPRESSLYPROVIDEDINANYWRITTENLICENSEAGREEMENTFROMMICROSOFT,THEFURNISHINGOFTHISDOCUMENTDOESNOTGIVEYOUANYLICENSETOTHESEPATENTS,TRADEMARKS,COPYRIGHTS,OROTHERINTELLECTUALPROPERTY2001MICROSOFTCORPORATIONALLRIGHTSRESERVEDMICROSOFT,ACTIVEX,FRONTPAGE,JSCRIPT,MSDOS,MSDN,OUTLOOK,POWERPOINT,VISUALBASIC,VISUALC,VISUALINTERDEV,VISUALSTUDIO,WINDOWS,WINDOWSMEDIAPLAYER,ANDWINDOWSNTAREEITHERREGISTEREDTRADEMARKSORTRADEMARKSOFMICROSOFTCORPORATIONINTHEUSAAND/OROTHERCOUNTRIESOTHERPRODUCTANDCOMPANYNAMESMENTIONEDHEREINMAYBETHETRADEMARKSOFTHEIRRESPECTIVEOWNERSMODULE3USINGADONETTOACCESSDATA1OVERVIEWOVERIEWOVERIEWOFADONETCONECTINGTOADATSOURCEACESINGDATWITHDATSETSUSINGSTOREDPROCEDURESACESINGDATWITHDATREADERSBINDIGTOXMLDATONEOFTHEREASONSFORTHEWIDESPREADUSEOFMICROSOFTACTIVESERVERPAGESASPISTHATITFACILITATESACCESSTODATASTORESASPNETEXPANDSONTHISCAPABILITYWITHTHEINTRODUCTIONOFADONET,WHICHOFFERSARICHSUITEOFDATAHANDLINGANDDATABINDINGFUNCTIONSFORMANIPULATINGALLTYPESOFDATAAFTERCOMPLETINGTHISMODULE,YOUWILLBEABLETODESCRIBETHEADONETOBJECTMODELCONNECTTOADATASOURCEBYUSINGADONETRETRIEVEDATAFROMADATABASEBYUSINGDATAREADERS,ANDDATASETSDISPLAYTHEDATAFROMADATABASEONTHECLIENTBYUSINGLISTBOUNDCONTROLSCUSTOMIZETHELOOKOFREPEATERCONTROLSWITHTEMPLATESUSESTOREDPROCEDURESTORETURNRECORDSETSREADDATAFROMANEXTENDEDMARKUPLANGUAGEXMLFILEINTODATASETSTHEREAREMANYCHANGESBETWEENTHEBETA1ANDBETA2VERSIONSOFASPNETWITHRESPECTTODATABINDINGFORADETAILEDLISTOFCHANGES,SEEAPPENDIXA,INCOURSE2063A,INTRODUCTIONTOASPNETNOTE2MODULE3USINGADONETTOACCESSDATAOVERVIEWOFADONETOVERIEWOFADONETTHEADONETOBJECTMODELANIMATIONUSINGADONETTOACESDATRECORDSETSVDATSETSUSINGNAMESPACESADONETISNOTAREVISIONOFMICROSOFTACTIVEXDATAOBJECTSADO,BUTANEWWAYTOMANIPULATEDATATHATISBASEDONDISCONNECTEDDATAANDXMLALTHOUGHADOISANIMPORTANTDATAACCESSTOOLWITHINASP,ITDOESNOTPROVIDEALLTHENECESSARYFEATURESFORDEVELOPINGROBUSTANDSCALABLEWEBAPPLICATIONSINSPITEOFADOSRICHOBJECTMODELANDRELATIVEEASEOFUSE,ITISCONNECTEDBYDEFAULT,RELIESONANOLEDBPROVIDERTOACCESSDATA,ANDITISENTIRELYCOMPONENTOBJECTMODELCOMBASEDADONETHASBEENDESIGNEDTOWORKWITHDISCONNECTEDDATASETSDISCONNECTEDDATASETSREDUCENETWORKTRAFFICADONETUTILIZESXMLASTHEUNIVERSALTRANSMISSIONFORMATTHISGUARANTEESINTEROPERABILITYASLONGASTHERECEIVINGCOMPONENTRUNSONAPLATFORMWHEREANXMLPARSERISAVAILABLEWHENTHETRANSMISSIONOCCURSTHROUGHXML,ITISNOLONGERNECESSARYTHATTHERECEIVERBEACOMOBJECTTHERECEIVINGCOMPONENTHASNOARCHITECTURALRESTRICTIONSWHATSOEVERANYSOFTWARECOMPONENTCANSHAREADONETDATA,ASLONGASITUSESTHESAMEXMLSCHEMAFORTHEFORMATOFTHETRANSMITTEDDATAINTHISSECTION,YOUWILLLEARNABOUTADONETYOUWILLLEARNABOUTTHENEWANDMODIFIEDOBJECTSINADONETYOUWILLALSOLEARNABOUTSOMEOFTHENEWNAMESPACESTHATAREINCLUDEDINASPNETMODULE3USINGADONETTOACCESSDATA3THEADONETOBJECTMODELTHEADONETOBJECTMODELDATSETCOMANDCONECTIONDATBASECOMANDASPXAGELISTBOUNDCNTRLDATREADERCOMPANYNORTHWINDTRDERSASPXAGEDATVIEWDATSETADONETEVOLVEDFROMTHEADODATAACCESSMODELBYUSINGADONET,YOUCANDEVELOPAPPLICATIONSTHATAREROBUSTANDSCALABLE,ANDTHATCANUSEXMLADONETHASSOMEOFTHESAMEOBJECTSASADOLIKETHECONNECTIONANDCOMMANDOBJECTS,ANDINTRODUCESNEWOBJECTS,SUCHASDATASETS,DATAREADERS,ANDDATASETCOMMANDSSOMEOFOBJECTSINADONETREPRESENTUPDATESOFEXISTINGOBJECTSSUCHASCONNECTIONANDCOMMAND,WHILEOTHERSARECOMPLETELYNEWSUCHASDATAREADER,DATASET,DATAVIEW,ANDDATASETCOMMANDCONNECTIONOBJECTSCONNECTIONOBJECTSAREUSEDTOTALKTODATABASESTHEYHAVEPROPERTIES,SUCHASDATASOURCE,USERID,ANDPASSWORD,THATARENEEDEDTOACCESSAPARTICULARDATASOURCECOMMANDSTRAVELOVERCONNECTIONS,ANDRESULTSETSARERETURNEDINTHEFORMOFSTREAMSTHATCANBEREADBYDATAREADERSORPUSHEDINTODATASETOBJECTSTHEREARETWOKINDSOFCONNECTIONOBJECTSINADONETSQLCONNECTIONANDADOCONNECTIONCOMMANDOBJECTSCOMMANDOBJECTSCONTAINTHEINFORMATIONTHATISSUBMITTEDTOADATABASEACOMMANDCANBEASTOREDPROCEDURECALL,ANUPDATESTATEMENT,ORASTATEMENTTHATRETURNSRESULTSYOUCANALSOUSEINPUTANDOUTPUTPARAMETERSANDRETURNVALUESINADONET,YOUCANUSETWOKINDSOFCOMMANDOBJECTSSQLCOMMANDANDADOCOMMAND4MODULE3USINGADONETTOACCESSDATADATAREADEROBJECTSADATAREADERISAREADONLY/FORWARDONLYVIEWONTHEDATAITPROVIDESASIMPLEANDLIGHTWEIGHTWAYOFTRAVERSINGTHROUGHRECORDSETSFOREXAMPLE,IFYOUWANTEDTOSIMPLYSHOWTHERESULTSOFASEARCHLISTINAWEBPA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