javascript - ECMAScript 6 类属性下划线前缀

Question

我见过的类模式几乎都是这样的:

class Foo {
    constructor(x, y, z) {
      this._x = x;
      this._y = y;
      this._z = z;
    }

    get x() {
      return this._x;
    }
    set x(value) {
      //I acctually do some stuff here
      this._x = value;
    }

    get y() {
      return this._y;
    }
    set y(value) {
      //I acctually do some stuff here
      this._y = value;
    }

    get z() {
      return this._z;
    }
    set z(value) {
      //I acctually do some stuff here
      this._z = value;
    }
}

console.log(new Foo('x', 'y', 'z')) 执行输出:

Foo { _x: 'x', _y: 'y', _z: 'z' }

console.log(JSON.stringify(new Foo('x', 'y', 'z'))) 执行输出:

{"_x":"x","_y":"y","_z":"z"}

这为我提供了带下划线前缀的字段，而我并不是为此而设计的，我如何才能让这些字段没有下划线前缀，同时让 getter 和 setter 由 instance.prop 交互触发。

Answer 1

您可以添加一个toJSON方法来调整JSON.stringify的输出

class Foo {
    constructor(x, y, z) {
      this._x = x;
      this._y = y;
      this._z = z;
    }

    get x() {
      return this._x;
    }
    set x(value) {
      this._x = value;
    }

    get y() {
      return this._y;
    }
    set y(value) {
      this._y = value;
    }

    get z() {
      return this._z;
    }
    set z(value) {
      this._z = value;
    }

    toJSON() {
      return {
        x: this._x,
        y: this._y,
        z: this._z
      };
    }
}

var foo = new Foo('x', 'y', 'z');
console.log(JSON.stringify(foo));

输出:"{"x":"x","y":"y","z":"z"}"