JavaScript - 面试题(1)

简单面试题

var age = 50
let obj = {
    age:20,
    sayHi() {
        console.log(this.age);  //20
        return function () {
            console.log(this.age);  //50
        }
    }
}
obj.sayHi()()

上面的 obj.sayHi()() 就相当于如下代码，是定义在window下的，要找到window下定义的全局变量age

var fn = obj.sayHi()
window.fn()

打印结果是