How to assign a method to the designer?

Question

I study JS, and noticed that after creating an object, an external function can be made its method, while a new element inside the object (for storing the function) is created right during assignment. If we want to add a function to the constructor, we can only assign an external function to an element that already exists in the constructor.

The question is - is there a way to create a new element in the constructor after its creation (and assign it a value, for example, a function)?

Here is an example. If I understand correctly, dog.newSound = changeSound; works because it is an object in animal.newSound = changeSound; It does not work because it is a constructor. Is there any other way to do the same for the constructor?

 //Конструктор function Animal(name, age, sound) { this.name = name; this.age = age; this.sound = sound; } //внешняя функция function changeSound(sound) { this.sound = sound; } //объект созданный с помощью конструктора var dog = new Animal("Jack", 5, "gav-gav") //создали переменную в объекте и присвоили ей функцию dog.newSound = changeSound; dog.newSound("woof-woof"); // вызвали функцию //пишем на страницу var here = document.getElementById("placeHere"); here.innerHTML = dog.sound;

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construction functions are usually called capitalized - Mikhail Vaysman

Accepted Answer · 2017-03-02T15:13:15

Use Animal.prototype to add methods to all objects of type Animal .

 //Конструктор function Animal(name, age, sound) { this.name = name; this.age = age; this.sound = sound; } Animal.prototype.newSound = changeSound; // !!! /* или без отдельной функции: Animal.prototype.newSound = function (sound) { this.sound = sound; } */ //внешняя функция function changeSound(sound) { this.sound = sound; } //объект созданный с помощью конструктора var dog = new Animal("Jack", 5, "gav-gav") //создали переменную в объекте и присвоили ей функцию //dog.newSound = changeSound; dog.newSound("cock-a-doodle-doo"); // вызвали функцию //пишем на страницу var here = document.getElementById("placeHere"); here.innerHTML = dog.sound;

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If after Animal.prototype some way to see what parameters the Animal constructor has - will the new function be included in the constructor?
Or Animal.prototype adds functionality to all objects created on the basis of the constructor but the constructor itself remains unchanged?
Constructor parameters - name, age, sound - between the parentheses.
The properties of this in no way are required to reflect these parameters.
Properties may be less or more, they may be called quite differently.
Thank you, that is, properties are internal variables of an object, and parameters are specific values that we give them when creating an object, right?
And the first option (to modify the constructor itself) is it not possible after its creation?

How to assign a method to the designer?

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