class Person {    constructor() {    }    private _name: string;    public get name() {        return this._name;    }    public set name(name: string) {        this._name = name;    }}let person = new Person();// person._name = "apple";  // 无法访问到_name变量person.name = "apple";console.log(person.name);  // 输出 apple　　

就是为了隔离类的自有属性和可暴露属性。