ES6: 21 Use getters and setters to Control Access to an Object


You can obtain values from an object, and set a value of a property within an object. These are classically called getters and setters. Getter functions are meant to simply return (get) the value of an object's private variable to the user without the user directly accessing the private variable. Setter functions are meant to modify (set) the value of an object's private variable based on the value passed into the setter function. This change could involve calculations, or even overwriting the previous value completely.
class Book {
constructor(author) {
this._author = author;
}
// getter
get writer(){
return this._author;
}
// setter
set writer(updatedAuthor){
this._author = updatedAuthor;
}
}
const lol = new Book('anonymous');
console.log(lol.writer);
lol.writer = 'wut';
console.log(lol.writer);
Notice the syntax we are using to invoke the getter and setter - as if they are not even functions. Getters and setters are important, because they hide internal implementation details.

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