super
Tavsif
super kalit so‘zi ota sinfning xususiyat va metodlaridan foydalanish maqsadida uning konstruktorini chaqirish uchun ishlatiladi.
Maslahat: "Vorislik" tushunchasini (ota va bola sinflar) yaxshiroq tushunish uchun JavaScript sinflari darsligimizni o‘qing.
Misol
extends kalit so‘zidan foydalanib, "Car" sinfidan metodlarni meros qilib oladigan "Model" nomli sinf yarating.
constructor metodida super() metodini chaqirish orqali biz ota sinfning constructor metodini chaqiramiz va ota sinfning xususiyat va metodlaridan foydalanish imkoniyatiga ega bo‘lamiz:
class Car {
constructor(brand) {
this.carname = brand;
}
present() {
return 'I have a ' + this.carname;
}
}
class Model extends Car {
constructor(brand, mod) {
super(brand);
this.model = mod;
}
show() {
return this.present() + ', it is a ' + this.model;
}
}
mycar = new Model("Ford", "Mustang");
document.getElementById("demo").innerHTML = mycar.show();
Brauzerlarda qo‘llab-quvvatlash
super — ECMAScript6 (ES6 2015) imkoniyati.
JavaScript 2015 2017-yil iyunidan beri barcha brauzerlarda qo‘llab-quvvatlanadi:
| Chrome 51 |
Edge 15 |
Firefox 54 |
Safari 10 |
Opera 38 |
| 2016-yil may | 2017-yil aprel | 2017-yil iyun | 2016-yil sentabr | 2016-yil iyun |
Sintaksis
super(arguments); // calls the parent constructor (only inside the constructor)
super.parentMethod(arguments); // calls a parent method
Texnik tafsilotlar
| JavaScript versiyasi: | ECMAScript 2015 (ES6) |
|---|
Tegishli sahifalar
JavaScript darsligi: JavaScript sinflari
JavaScript darsligi: JavaScript ES6 (EcmaScript 2015)
JavaScript ma’lumotnomasi: extends kalit so‘zi
JavaScript ma’lumotnomasi: constructor() metodi
W3Schools Pathfinder
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