JavaScript私有属性的实现方式及对比详解

function Person(name) {
    let _name = name; // 私有属性
 
    this.getName = function() {
        return _name;
    };
 
    this.setName = function(newName) {
        _name = newName;
    };
}
 
const person = new Person("Alice");
console.log(person.getName()); // 输出: Alice
console.log(person._name); // 输出: undefined (无法直接访问)

const _name = Symbol('name');
 
class Person {
    constructor(name) {
        this[_name] = name;
    }
 
    getName() {
        return this[_name];
    }
}
 
const person = new Person("Bob");
console.log(person.getName()); // 输出: Bob
console.log(person[_name]); // 可以访问，但需要知道 Symbol 值

const _name = new WeakMap();
 
class Person {
    constructor(name) {
        _name.set(this, name);
    }
 
    getName() {
        return _name.get(this);
    }
}
 
const person = new Person("Charlie");
console.log(person.getName()); // 输出: Charlie
console.log(person._name); // 输出: undefined (无法直接访问)

class Person {
    #name; // 私有属性
 
    constructor(name) {
        this.#name = name;
    }
 
    getName() {
        return this.#name;
    }
}
 
const person = new Person("David");
console.log(person.getName()); // 输出: David
console.log(person.#name); // 报错: 无法访问私有属性