Learn all about Partial Class in C# | Simplilearn

Partial Class is a unique feature of C#. It can break the functionality of a single class into many files. When the application is compiled, ... 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PartialClassisauniquefeatureofC#.Itcanbreakthefunctionalityofasingleclassintomanyfiles.Whentheapplicationiscompiled,thesefilesarethenreassembledintoasingleclassfile.Thepartialkeywordisusedtobuildapartialclass.  PostGraduateProgram:FullStackWebDevelopmentinCollaborationwithCaltechCTMEEnrollNow UseofPartialClasses Followingarethescenarioswheresplittingthefilesbecomesnecessary: Ifyouareworkingonabiggerproject,splittingthefilesoverdifferentclasseshelpsdevelopersworkonthesameprojectsimultaneously. Ifyouareworkingonanautomaticallygeneratedsource,thenthecodecanbeaddedtotheclasswithoutregeneratingthesourcefile. Thevisualstudiowhichcreateswindowsforms,webservicewrappercode,andsomeotherfilesautomatically,usesthispartialclassmethodtosplititintofileswithoutmodifyingthem. Partialclassescanbehelpfulifyouareusingsourcegeneratorstogenerateadditionalfunctionality. Wecansplittheclassdefinitionbyusingthepartialkeywordmodifierasshownintheimagebelow. Thepartialkeyworddenotesthatotherpartsofclass,method,andfunctioncanbedefinedhere.  publicpartialclassStudents{     privatestringName;     privateintRollno;     publicStudents(stringa,intt)     {         this.Student_name=a;         this.Roll_no=t;     } } Listedbelowaresomeofthefiletypeswhicharemergedfromthepartialclasses: XMLcomments interfaces generic-typeparameterattributes classattributes members NewCourse:FullStackDevelopmentforBeginnersLearnGitCommand,Angular,NodeJS,Maven&MoreEnrollNow AdvantagesofaPartialClass 1.Withthehelpofpartialclasses,youcanseparateUIdesigncodeandbusinesslogiccode. Forinstance,ifwedevelopawebapplicationusingthevisualstudio,someofthesourcefileswillgetadded.Thesefileswillhavepartialkeywords.Thereisa".aspx.cs"classthathasthebusinesslogiccodeand"aspx.designer.cs"thathasuserinterfacecontroldefinition. 2.Wearenotrequiredtoregeneratethesourcefilewhenworkingwithautomatically-generatedfiles.  Forinstance,whenworkingwithLINQtoSQLandcreatingaDBMLfile.Whenwecopyandpasteatable,itwillcreateapartialclassindesigner.cs.Sotonotaddnewcolumns,wecancreateaseparatesourcefilefortheclass,whichwillactasapartialclass. 3.Moredeveloperscanworksimultaneouslyonthesameproject. 4.Itiseasiertomaintain,understand,anddevelopapartialclassthanahugeclassforthewholeprogram.Ahugefilecanbeconvertedintomanypartialclassescontainingvariousmethodsandclasses. PointstoRemember Allpartialclassesmustcontainthepartialkeyword. Partialclassescanelaborateonvariousbaseclassesthatwillbecombinedatthecompilertime.Anymethod,interface,andfunctiondeclaredonapartialclassisavailableforalltheotherparts. Thesourcefilenameforeachpartofthepartialclasscanbedifferent,buteachpartialclass’snamemustbethesame. Thenameofallpartsofapartialclassshouldbethesame. Allpartsofapartialclassshouldbeinthesameassembly. Allclassesshouldhavepublic,private,oranotheraccessibilitymodifier;theaccessibilityofeachpartofthepartialclassshouldbethesame.  Ifweinheritaclassormethodonapartialclass,itwillalsobeinheritedforallpartsofthepartialclass. Ifanypartoftheclassisdeclaredwithanyspecificaccessmodifier,thenthewholeclasswillbeconsideredofthesametype.  Ifanypartoftheclassisdeclaredabstract,thenthewholetypeisabstract,andifanyclassisdeclaredsealed,thewholeclassissealed.  Example: Wewillcreateapartialclassthatwillhelpusunderstandtheuseofpartialclassesinourprojects.  Inthisexample,weareworkingwithLINQtoSQLapplicationstocreateName,Rollno,andDateofBirthcolumnsforstudents.WewillthencreateaseparatepartialclasswithaRollnoproperty. 1.Createa"Student"tableinthedatabase. Wewillneedtocreateastudenttableinthedatabasethathasthethreefields"Name","RollNo",and"DateOfBirth".The"Name"fieldistheprimarykey. CREATETABLEStudent   ( Classintidentity(1,1)primarykey,   Namenvarchar(50),     DateOfBirthDatedefaultgetUtcDate()  )  2.Wewillcreateawebapplicationfromthevisualstudio. 3.Next,wewilladdanewclassusingtheaddfunctiononthesolutionexplorer. 4.Choose"LINQtoSQLClasses"fromthelistofpartialclassesandprovidethename"Student"fortheDBMLname.Thenwewillclickon"Add". 5.WewillthencopytheUsertablefromthedatabaseintheServerExplorerandpasteitintotheDesignersurfaceofthe"Student.dbml"file. 6.Nowwecanopenthe"Student.designer.cs"file.Weseethe"Student"partialclasshasbeencreated.Wecannowdraganddropa"Student"tablefromthedatabaseonthesurface. 7.CreateaUIdesigntoshowstudents’detailsinthegridviewfromthedataprovided.                        

FullStackWebDeveloperCourseTobecomeanexpertinMEANStackViewCourse 8.Wewillwritecodeforthe"Page_Load"eventtobindagridviewbystudentlistinthecodebehindthefile. usingSystem;   usingSystem.Linq;   namespacePartialClassExample     {   publicpartialclassStudentUI:System.Web.UI.Page   {       protectedvoidPage_Load(objectsender,EventArgse)       {           using(StudentDataContextcontext=newStudentDataContext())           {               varquery=fromstudentincontext.GetTable()                    selectnew                        {                              student.Name,                            student.DateOfBirth,                            student.RollNo                         };                varcontent=query.ToList();                   gridStudent.DataSource=content;                   gridStudent.DataBind();            }        }    }      } 9.Onrunningthisapplication,wewillseetheRollnocolumninthegridviewthatwillshoweachstudent’sage. AdvanceyourcareerasaMEANstackdeveloperwiththe FullStackWebDeveloper-MEANStackMaster'sProgram.Enrollnow! Conclusion InthisarticleonPartialClassinC#,welearnedthatwiththehelpofpartialclasses,wecansplitourclassesintomultiplefiles.Thisisuseful,especiallywheneithertheclassdefinitionislargeorwhenyouareworkingonacomplexmodelormethod,likewithWinFormsinVisualStudiodesigner.WealsosawtheadvantagesofusingPartialClassinC#andsomemajorkeypointstorememberaboutPartialClassinC#. ToknowmoreaboutpartialclassinC#,youcanenrollinthePost-GraduateProgramInFull-StackWebDevelopmentofferedbySimplilearnincollaborationwithCaltechCTME.ThisWebDevelopmentcourseisadescriptiveonlinebootcampthatincludes25projects,acapstoneproject,andinteractiveonlineclasses.InadditiontoASP.NET,thecoursealsodetailseverythingyouneedtobecomeafull-stacktechnologistandaccelerateyourcareerasasoftwaredeveloper. Simplilearnalsooffersfreeonlineskill-upcoursesinseveraldomains,fromdatascienceandbusinessanalyticstosoftwaredevelopment,AI,andmachinelearning.Youcantakeupanyofthesefreecoursestoupgradeyourskillsandadvanceyourcareer. FindourPostGraduatePrograminFullStackWebDevelopmentOnlineBootcampintopcities:NameDatePlacePostGraduatePrograminFullStackWebDevelopmentCohortstartson29thSep2022,WeekendbatchYourCityViewDetailsPostGraduatePrograminFullStackWebDevelopmentCohortstartson13thOct2022,WeekendbatchSingaporeViewDetailsPostGraduatePrograminFullStackWebDevelopmentCohortstartson6thDec2022,WeekendbatchYourCityViewDetailsAbouttheAuthorSimplilearnSimplilearnisoneoftheworld’sleadingprovidersofonlinetrainingforDigitalMarketing,CloudComputing,ProjectManagement,DataScience,IT,SoftwareDevelopment,andmanyotheremergingtechnologies.ViewMoreRecommendedProgramsPostGraduatePrograminFullStackWebDevelopment3827LearnersLifetimeAccess*FullStackWebDeveloper-MEANStack1098LearnersLifetimeAccess**Lifetimeaccesstohigh-quality,self-pacede-learningcontent.ExploreCategoryFindPostGraduatePrograminFullStackWebDevelopmentinthesecitiesPostGraduatePrograminFullStackWebDevelopment,SingaporeNextArticleUnderstandingtheFriendClassinC++ByRavikiranAS15317Sep16,2022RecommendedResourcesFreeeBook:SalesforceDeveloperSalaryReportEbookAComprehensiveLookatClassesandObjectsinC++ArticleAllYouNeedtoKnowAboutClassesinC++VideoTutorialTheStateofUpskillingin2022EbookAbstractClassinc++ArticleTheDifferenceBetweenC++andCVideoTutorialprevNext DisclaimerPMP,PMI,PMBOK,CAPM,PgMP,PfMP,ACP,PBA,RMP,SP,andOPM3areregisteredmarksoftheProjectManagementInstitute,Inc.