Professional Visual Basic 2008

1452 Pages·2008·21.262 MB·English

by  Bill Evjen, et al

Professional
Visual Basic® 2008
Bill Evjen
Billy Hollis
Bill Sheldon
Kent Sharkey
WileyPublishing,Inc.
®
Professional Visual Basic 2008
Publishedby
WileyPublishing,Inc.
10475CrosspointBoulevard
Indianapolis,IN46256
www.wiley.com
Copyright©2008byWileyPublishing,Inc.,Indianapolis,Indiana
PublishedsimultaneouslyinCanada
ISBN:978-0-470-19136-1
ManufacturedintheUnitedStatesofAmerica
10987654321
LibraryofCongressCataloging-in-PublicationData:
ProfessionalVisualbasic2008/BillEvjen...[etal.].
p.cm.
Includesindex.
ISBN978-0-470-19136-1(paper/website)
1. MicrosoftVisualBASIC2. BASIC(Computerprogramlanguage) I.Evjen,Bill.
QA76.73.B3P748762008
005.2’762--dc22
2008004975
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Evjen-91361 fauth.tex V1-04/01/2008 3:10pm Pagev
About the Authors
BillEvjenisanactiveproponentof.NETtechnologiesandcommunity-basedlearninginitiativesfor
.NET.Hehasbeenactivelyinvolvedwith.NETsincethefirstbitswerereleasedin2000.Inthesameyear,
BillfoundedtheSt.Louis.NETUserGroup(www.stlnet.org),oneoftheworld’sfirstsuchgroups.Bill
isalsothefounderandformerexecutivedirectoroftheInternational.NETAssociation(www.ineta.org),
whichrepresentsmorethan500,000membersworldwide.
BasedinSt.Louis,Missouri,BillisanacclaimedauthorandspeakeronASP.NETandXMLWebServices.
Hehasauthoredorco-authoredmorethan15books,includingProfessionalASP.NET3.5,Professional
C#2008,ASP.NETProfessionalSecrets,XMLWebServicesforASP.NET,andWebServicesEnhancements:
UnderstandingtheWSEforEnterpriseApplications(allpublishedbyWiley).Inadditiontowriting,Billisa
speakeratnumerousconferences,includingDevConnections,VSLive,andTechEd.Healsoworksclosely
withMicrosoftasaMicrosoftRegionalDirectorandanMVP.
BillisthetechnicalarchitectforLipper(www.lipperweb.com),awhollyownedsubsidiaryofReuters,the
internationalnewsandfinancialservicescompany.HegraduatedfromWesternWashingtonUniversity
inBellingham,Washington,withaRussianlanguagedegree.Whenheisn’ttinkeringonthecomputer,he
canusuallybefoundathissummerhouseinToivakka,[email protected].
The.NETFramework3.5releasecamequicklyforuswriters,anditwouldn’thavebeenpossibletoproducethis
bookasfastaswedidifitweren’tforthededicationoftheteamsbuiltforit.TremendousthankstoKatieMohrfor
beingmorethanpatientwithmeingettingthisandsomeother.NET3.5booksoutthedoor.Also,bigthanksgo
outtoKevinKentfordoinghisbesttohelpingmestayonschedule.
Finally,totheoneswhopaidthebiggestpriceforthiswritingsession—mywife,Tuija,andourthreekids:Sofia,
Henri,andKalle—thanksforallyoudo!
BillyHollisisanauthorandsoftwareconsultantbasedinNashville,Tennessee.Billywasco-authorof
thefirstbookeverpublishedonVisualBasic.NET,aswellasmanyotherbooksonsoftwaredevelop-
ment.HeisamemberoftheMicrosoftRegionalDirectorprogramandaMicrosoftMVP.In2002,Billy
wasselectedasoneoftheoriginal.NET‘‘SoftwareLegends.’’Heisheavilyinvolvedwithconsulting,
training,anddevelopmentonthe.NETplatform,focusingonarchitecture,smart-clientdevelopment,
commercialpackages,anduser-interfacetechnologies.Heregularlyspeaksonsoftwaredevelopmentat
majorconferencesallovertheworld,includingMicrosoft’sPDCandTechEdevents,DevConnections,
VSLive,andarchitectureeventssuchasthePatternsandPracticesArchitectSummit.
Iowetremendousthankstomyfamily,whohavesomehowlearnedtoputupwithmarathonwritingsessions,and
tomybusinesspartner,GaryBailey,forkeepingourclientshappywhileI’mwriting.
BillSheldonisasoftwarearchitectandengineer,originallyfromBaltimore,Maryland.Holdingadegree
incomputersciencefromtheIllinoisInstituteofTechnology(IIT),Billhasbeenactivelyemployedasa
softwareengineersinceresigninghiscommissionwiththeUnitedStatesNavy.HeisaMicrosoftMVP
forVisualBasicemployedasaprincipalengineerwithInterKnowlogyinCarlsbad,California,andworks
asaninstructorforVisualBasic–relatedcoursesattheUniversityofCaliforniaSanDiegoExtension.
Inadditiontowritingbooks,Billhaspublisheddozensofarticles,includingtheDeveloperUpdate
Newsletter,SQLServerMagazinefeaturearticles,andotherPentonpublications.Heisanestablished
online presenter for MSDN and speaks at live events such as VSLive, DevConnections, Office
Evjen-91361 fauth.tex V1-04/01/2008 3:10pm Pagevi
About the Authors
DevelopersConference,andcommunityeventssuchasusergroupsandcodecamp.Billisanavidcyclist
andisactiveinthefightagainstdiabetes.
Tomywonderfulwife,Tracie,whoisforcedtocarryonwhileIisolatemyselftoconcentrateonwriting.Andtothe
nextgenerationofchildrenwhohavejoinedourextendedSheldonfamily(myownandmybrothers’)inthepastfive
years—Nick,Elena,Ben,BillyV,Abigail,andournextson(thisspring’scomingattraction)—eachandevery
oneofyouisavaluablepartofourlives.
KentSharkeyisanindependentconsultantwholivesandcodesinComox,BritishColumbia.Before
goingsolo,KentworkedatMicrosoftasatechnicalevangelistandcontentstrategist,promotingthe
useof.NETtechnologies.Heliveswithhiswife,Margaret,andthree‘‘children’’— Squirrel,Cica,
andToffee.
ToBabi,forkeepingmealiveandputtingupwithme—hopefully,foralongtimetocome.
vi
Evjen-91361 ftech.tex V1-04/01/2008 3:11pm Pagevii
About the Technical Editors
MarkLavoieistheinformationsystemmanagerforamidsizedinsurancecompanylocatedinCharlotte,
NorthCarolina.MarkhasworkedwithMicrosoftproductsandtechnologiesfornineyears.Hehas
workedasaconsultant,managedITprojects,anddesignedandprogrammedcustomapplications.Heis
anativeofCanadaand,whennotworking,enjoyscookingandvacationingwithhiswonderfulwife.
ToddMeisterhasbeendevelopingusingMicrosofttechnologiesforovertenyears.He’sbeenatech-
nicaleditorformorethan40titles,rangingfromSQLServertothe.NETFramework.Besidestech-
nicalediting,heisanassistantdirectorforComputingServicesatBallStateUniversityinMuncie,
Indiana.Hislatestdevelopmentaccomplishmentwasdevelopingane-commercesitefromscratch,which
includedover15,000linesof.NETcode,creditcardintegration,giftcertificatefunctionality,anddis-
countcodes.Heliveswithhiswife,Kimberly,andtheirfourchildrenincentralIndiana.ContactToddat
[email protected].
AndrewMooreisagraduateofPurdueUniversity–CalumetinHammond,Indiana,andhasbeendevel-
opingsoftwaresince1998forradarsystems,airtrafficmanagement,discrete-eventsimulation,and
businesscommunicationsapplicationsusingC,C++,C#,andJavaontheWindows,UNIX,andLinux
platforms.AndrewistheauthoroftwoWroxBloxtitles:‘‘CreateAmazingCustomUserInterfaceswith
WPF,C#,andXAMLin.NET3.0’’(www.wrox.com/WileyCDA/WroxTitle/productCd-0470258713.html)
and‘‘.NET3.5CDAudioPlayer.’’HeiscurrentlyworkingasasoftwareengineeratInteractiveIntelli-
gence,Inc.,inIndianapolis,Indiana,developingMicrosoft-basedapplicationsforbusinesscommunica-
tions.AndrewlivesinIndianawithhiswife,Barbara,andtheirtwochildren,SophiaandAndrew.
Evjen-91361 fcre.tex V1-04/01/2008 3:11pm Pageix
Credits
AcquisitionsEditor ProductionManager
KatieMohr TimTate
SeniorDevelopmentEditor VicePresidentandExecutiveGroup
KevinKent Publisher
RichardSwadley
TechnicalEditors
MarkLavoie VicePresidentandExecutive
ToddMeister Publisher
AndrewMoore JosephB.Wikert
ProductionEditor ProjectCoordinator,Cover
WilliamA.Barton LynseyStanford
CopyEditor Proofreaders
LuannRouff EdwardMoyer,PaulSagan,WordOne
EditorialManager Indexer
MaryBethWakefield RobertSwanson
Evjen-91361 ftoc.tex V1-04/01/2008 3:12pm Pagexi
Contents
Introduction xxxi
Chapter 1: Visual Basic 2008 Core Elements 1
InitialKeywordsandSyntax 2
ConsoleApplications 5
ValueandReferenceTypes 8
PrimitiveTypes 10
Commands:Conditional 11
IfThen 12
ComparisonOperators 12
SelectCase 14
ValueTypes(Structures) 15
Boolean 15
IntegerTypes 16
UnsignedTypes 17
DecimalTypes 18
CharandByte 20
DateTime 21
ReferenceTypes(Classes) 21
TheObjectClass 21
TheStringClass 22
TheDBNullClassandIsDBNullFunction 25
NullableTypes 26
Arrays 27
Collections 30
Commands:LoopingStatements 32
ForEachandForNext 32
While,DoWhile,andDoUntil 33
Boxing 34
ParameterPassing 35
ParamArray 36
VariableScope 37
DataTypeConversions 38
ImplicitConversionsandCompilerOptions 39
Evjen-91361 ftoc.tex V1-04/01/2008 3:12pm Pagexii
Contents
XMLLiterals 42
PerformingExplicitConversions 44
Summary 47
Chapter 2: Object Syntax Introduction 49
Object-OrientedTerminology 50
Objects,Classes,andInstances 50
CompositionofanObject 50
WorkingwithObjects 54
ObjectDeclarationandInstantiation 54
ObjectReferences 55
DereferencingObjects 56
EarlyBindingversusLateBinding 56
CreatingClasses 60
BasicClasses 60
ConstructorMethods 79
TerminationandCleanup 80
AdvancedConcepts 81
OverloadingMethods 81
OverloadingConstructorMethods 84
SharedMethods,Variables,andEvents 85
OperatorOverloading 90
Delegates 93
ClassesversusComponents 98
Summary 99
Chapter 3: Object-Oriented Programming 101
Inheritance 102
ImplementingInheritance 104
PreventingInheritance 151
MultipleInterfaces 151
ObjectInterfaces 151
SecondaryInterfaces 152
Abstraction 159
Encapsulation 162
Polymorphism 165
MethodSignatures 165
ImplementingPolymorphism 165
Inheritance 176
WhentoUseInheritance 176
InheritanceandMultipleInterfaces 180
xii
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Contents
HowDeeptoGo? 186
TheFragileBaseClassProblem 187
Summary 190
Chapter 4: The Common Language 193
Elementsofa.NETApplication 194
Modules 194
Assemblies 195
Types 196
VersioningandDeployment 197
BetterSupportforVersioning 197
BetterDeployment 198
Cross-LanguageIntegration 199
TheCommonTypeSystem 199
Metadata 200
BetterSupportforMetadata 201
Attributes 201
TheReflectionAPI 204
ILDisassembler 204
MemoryManagement 205
TraditionalGarbageCollection 206
FasterMemoryAllocationforObjects 213
GarbageCollectorOptimizations 215
Summary 217
Chapter 5: Localization 219
CulturesandRegions 219
UnderstandingCultureTypes 220
LookingatYourThread 221
DeclaringCultureGloballyinASP.NET 224
AdoptingCultureSettingsinASP.NET 225
TranslatingValuesandBehaviors 226
UnderstandingDifferencesinDates 227
UnderstandingDifferencesinNumbersandCurrencies 228
UnderstandingDifferencesinSortingStrings 231
WorkingwithASP.NETResourceFiles 233
MakingUseofLocalResources 234
MakingUseofGlobalResources 240
ResourceFilesinWindowsForms 242
Summary 246
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Evjen-91361 ftoc.tex V1-04/01/2008 3:12pm Pagexiv
Contents
Chapter 6: Generics 247
UsingGenerics 247
GenericTypes 249
GenericMethods 254
CreatingGenerics 255
GenericTypes 255
GenericMethods 264
Constraints 265
GenericsandLateBinding 268
Summary 269
Chapter 7: Namespaces 271
WhatIsaNamespace? 272
NamespacesandReferences 275
CommonNamespaces 277
ImportingandAliasingNamespaces 280
ImportingNamespaces 280
AliasingNamespaces 282
ReferencingNamespacesinASP.NET 282
CreatingYourOwnNamespaces 283
TheMyKeyword 286
My.Application 287
My.Computer 291
My.FormsNamespace 294
My.Resources 294
My.User 295
My.WebServices 295
ExtendingtheMyNamespace 295
Summary 297
Chapter 8: Exception Handling and Debugging 299
ABriefReviewofErrorHandlinginVB6 300
Exceptionsin.NET 301
ImportantPropertiesandMethodsofanException 301
HowExceptionsDifferfromtheErrObjectinVB6 302
StructuredException-HandlingKeywords 302
TheTry,Catch,andFinallyKeywords 303
TheThrowKeyword 305
ThrowingaNewException 306
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