资源描述：
《计算机科学与技术：VB.NET应用教程 978-7-302-09622-1 Advanced VB.NET Chapter 4》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、Chapter4ADetailedLookatObjectOrientationObjectivesObjectOrientedProgrammingConceptsEncapsulationInheritancePolymorphismVB.NETimplementationofOOPCreatingClasseswithProperties,Methods,andEventsUsingClassinstancesLabExercise4.1AdditionalOOTopicsSuggestedHomeAssignments2Copyright2004PearsonEducation,Inc
2、.EncapsulationVB.NETiscompletelyobjectoriented.Ex:TheFormisasubclassthatinheritsfromtheFormsuperclassAClasscontainsdefinitionsforProperties,Methods,anddeclarationsforEvents.Externalprojectmodulescannotalteraclass;butcanonlyconsumeinstancesofaclass.ThisfeatureiscalledEncapsulation3Copyright2004Pearso
3、nEducation,Inc.InheritanceTheabilityofasubclasstoinherittheproperties,methods,andeventsfromasuperclassisknownasInheritanceEarlierversionsofVBdidnotsupportInheritance.SinceVB.NETiscompletelyobjectoriented,inheritanceissupported4Copyright2004PearsonEducation,Inc.PolymorphismTheabilitytocreateprocedure
4、sthatcanoperateonobjectsfrommorethanoneclassisknownasPolymorphismPolymorphismallowsthemethodsindifferentclasseshavethesamenameevenifthosemethodsperformdifferenttasks5Copyright2004PearsonEducation,Inc.NamespacesLogicalgroupingofVB.NETclassesisknownasNamespaces Ex:TheFormclassbelongstoSystems.Windows.
5、FormsnamespaceRequirednamespacescanbeincludedinaprojectusingtheImportskeywordImportsInventory.MechanicalDimobjPartAsNewPart6Copyright2004PearsonEducation,Inc.ObjectivesObjectOrientedProgrammingConceptsEncapsulationInheritancePolymorphismVB.NETimplementationofOOPCreatingClasseswithProperties,Methods,
6、andEventsUsingClassinstancesLabExercise4.1AdditionalOOTopicsSuggestedHomeAssignments7Copyright2004PearsonEducation,Inc.DesigningaClassModuleFigure4.1.AddingaNewClass8Copyright2004PearsonEducation,Inc.DesigningaClassModule–Cont.ClassesaredefinedusingaPublicClass…EndClassstructurePublicClassClass1---P
7、roperty,Method,andEventDefinitions---EndClass9Copyright2004PearsonEducation,Inc.DesigningaClassModule–PropertiesClassPropertiesaredefinedusingGet…EndGetandSet…EndSetstructures.ThekeywordPublicmustbeus
