C# Classes and Objects - W3Schools

Everything in C# is associated with classes and objects, along with its attributes and methods. ... prog2.cs. class Car { public string color = "red"; } ... 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EverythinginC#isassociatedwithclassesandobjects,alongwithits attributesand methods.Forexample:inreallife,acarisanobject.Thecarhas attributes,suchasweightandcolor,and methods,suchasdriveandbrake. AClassislikeanobjectconstructor,ora"blueprint"forcreatingobjects. CreateaClass Tocreateaclass,usetheclasskeyword: Createaclassnamed"Car"withavariablecolor: classCar {  stringcolor="red"; } Whenavariableisdeclareddirectlyinaclass,itisoftenreferredtoasa field(orattribute). Itisnotrequired,butitisagoodpracticetostartwithanuppercasefirstletterwhennamingclasses.Also,itiscommonthatthenameoftheC#fileandtheclassmatches,asitmakesourcodeorganized.Howeveritisnotrequired(likeinJava). CreateanObject Anobjectiscreatedfromaclass.Wehavealreadycreatedtheclassnamed Car, sonowwecanusethistocreateobjects. TocreateanobjectofCar, specifytheclassname,followedbytheobjectname,andusethekeywordnew: Example Createanobjectcalled"myObj"anduse ittoprintthevalueof color: classCar {  stringcolor="red";  staticvoidMain(string[]args) {    CarmyObj=newCar();    Console.WriteLine(myObj.color);  } } TryitYourself» Notethatweusethedotsyntax(.)toaccessvariables/fieldsinsideaclass(myObj.color).Youwilllearnmoreabout fieldsinthenextchapter. MultipleObjects Youcancreatemultipleobjectsofoneclass: Example CreatetwoobjectsofCar: classCar { stringcolor="red"; staticvoidMain(string[]args) { CarmyObj1=newCar(); CarmyObj2=newCar(); Console.WriteLine(myObj1.color); Console.WriteLine(myObj2.color); } } TryitYourself» UsingMultipleClasses Youcanalsocreateanobjectofaclassandaccessitinanotherclass.This isoftenusedforbetterorganizationofclasses(oneclasshasallthe fieldsandmethods,whiletheotherclassholdstheMain()method(codeto beexecuted)). prog2.cs prog.cs prog2.cs classCar {  publicstringcolor="red"; } prog.cs classProgram { staticvoidMain(string[]args) { CarmyObj=newCar(); Console.WriteLine(myObj.color); } } TryitYourself» Didyounoticethepublickeyword?Itiscalledanaccessmodifier, whichspecifiesthatthecolorvariable/fieldofCarisaccessibleforotherclassesaswell,suchas Program. Youwilllearnmuchmoreaboutaccessmodifiersandclasses/objectsinthenextchapters. ❮Previous Next❯ NEW WejustlaunchedW3Schoolsvideos Explorenow COLORPICKER Getcertifiedbycompletingacoursetoday! w3schoolsCERTIFIED.2022 Getstarted CODEGAME PlayGame