class Person { constructor () { // 在非继承类 的constructor 中使用super 会报错 super() // SyntaxError: 'super' keyword unexpected here } methods () { console.log(super.text) // undefined } static staticMethods () { console.log(super.text) // undefined } } 1. 2. 3. 4. 5. 6. ...
JavaScript Tutorial:JavaScript ES6 (EcmaScript 2015) JavaScript Reference:The super Keyword JavaScript Reference:The constructor() method ❮PreviousJavaScript ClassReferenceNext❯ Track your progress - it's free! Log inSign Up COLOR PICKER
set函数和get函数是设置在属性的 Descriptor 对象上的,可以通过 Object.getOwnPrototyDescriptor 来获取指定属性的指定描述对象。 javascript 代码解读 复制代码 constdescriptor =Object.getOwnPropertyDescriptor(Person.prototype,'prop')'get'indescriptor// true'set'indescriptor// true Generator 方法 如果某个方法之...
_firstNamefirstName_lastNamelastName_ageageObject_firstName_firstNamevalue"LastName":{get:function(){return_lastName},set:function(value){_lastName=value}},"Age":{get:function(){return_age},set:function(value){_age=value}}});this.getFullName=function(){returnthis.FirstName+" "+this.Last...
JavaScript super() keyword Thesuperkeyword used inside a child class denotes its parent class. For example, // parent classclassPerson{constructor(name) {this.name = name; } greet() {console.log(`Hello${this.name}`); } }// inheriting parent classclassStudentextendsPerson{constructor(name) ...
The static keyword defines static methods for classes.Static methods are called directly on the class (Car from the example above) - without creating an instance/object (mycar) of the class.Browser Supportstatic is an ECMAScript6 (ES6) feature....
# python code to demonstrate example of# class keyword# student class code in Python# class definitionclassStudent:__id=0__name=""__course=""# function to set datadefsetData(self,id,name,course):self.__id=idself.__name=name self.__course=course# function to get/print datadefshowData...
classFather{test(){return0;}statictest1(){return1;}}classChildextendsFather{constructor(){super();}}classChild1extendsFather{test2(){super();//Uncaught SyntaxError: 'super' keyword unexpected//here}} 调用父类方法, super 作为对象,在普通方法中,指向父类的原型对象,在静态方法中,指向父类 ...
Again, even if our rectangle class did not have a constructor, we'd still need to call super within the square's constructor because it is required when we're working with subclasses that have constructors and when thethiskeyword is used in the constructor. ...
TypeScript fully supports theclasskeyword introduced by ES2015. Like other JavaScript language features, TypeScript provides type annotations and other syntax, allowing you to express the relationship between classes and other types. Class Members ...