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<html lang="en">
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<meta charset="UTF-8">
<title>04_对象扩展</title>
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<!--
1. Object.is(v1, v2)
* 判断2个数据是否完全相等
2. Object.assign(target, source1, source2..)
* 将源对象的属性复制到目标对象上
3. 直接操作 __proto__ 属性
let obj2 = {};
obj2.__proto__ = obj1;
-->
<script type="text/javascript">
console.log(Object.is('abc', 'abc')); // true
console.log(NaN == NaN); // false
console.log(Object.is(NaN, NaN)); // true
console.log(0 == -0);// true
console.log(Object.is(0, -0)); // false
// Object.assign(target, source1, source2..)
let obj = { name: 'kobe', age: 39, c: { d: 2 } };
let obj1 = {};
Object.assign(obj1, obj);
console.log(obj1, obj1.name); // {name: "kobe", age: 39, c: {d: 2}} "kobe"
// 直接操作 __proto__ 属性
let obj3 = { name: 'anverson', age: 41 };
let obj4 = {};
obj4.__proto__ = obj3;
console.log(obj4, obj4.name, obj4.age); // {} "anverson" 41
</script>
</body>
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