es6 javascript setter函数外部构造

Question

is it possible to call the setter function outside the constructor class?

ie i have the following class

class example {
  constructor() {
    this._partner = 0;
   }
   get partner() {
    return this._partner;
   }

  set partner(id) {
    this._partner = id;
  }
}

when i call

friends = new example();
freinds.partner(75);

i see the follwing error:

 Uncaught TypeError: example.partner is not a function

Answer 1

To invoke a setter/getter, it has to look from the outside as if you're directly setting or retrieving a property on the object (not calling a function):

 class example { constructor() { this._partner = 0; } get partner() { console.log('getter running'); return this._partner; } set partner(id) { console.log('setter running'); this._partner = id; } } friends = new example(); console.log('about to assign to .partner'); friends.partner = 75; console.log('about to retrieve .partner'); console.log(friends.partner); 

Note that the parameter that the setter sees is the value that looks like got "assigned" to the property outside.

Answer 2

这些setter和getter使您可以直接使用属性（无需使用括号）

friends.partner = 75;