1. var obj = {
    2.   name: 'AAA',
    3.   age: 23,
    4.   address: '广州'
    5. }
    6. Object.defineProperty(obj, Symbol.iterator, {
    7.   writable: false,
    8.   enumerable: false,
    9.   configurable: true,
    10.   value: function() {
    11.     var self = this;
    12.     var index = 0;
    13.     var keys = Object.keys(self);
    14.     return {
    15.       next: function() {
    16.         return {
    17.           value: self[keys[index++]],
    18.           done: index > keys.length
    19.         }
    20.       }
    21.     }
    22.   }
    23. })
    24. for (const val of obj) {
    25.   console.log(`属性值为：${val}`);
    26. }