es6 - 箭头

class User {
    constructor(name, age) {
        this.name = name;
        this.age = age;
    }

    changeName(name) {
        this.name = name;
    }

    changeAge(age) {
        this.age = age;
    }

    chage(name, age) {

        // 本this -> 获取的是全局的this
        var self = this;
        let fn = () => {
　　　　　　//无论嵌套多少层 -> 只要通过箭头符号获取的就是全局的
            (() => {
                (() => {
                    (() => {
                        console.log('全局this：', self);
                        this.changeAge(age);
                        this.changeName(name);
                    })();
                })()
            })()

            console.log('全局this：', self);
            this.changeAge(age);
            this.changeName(name);
        }

        // function fn() {
        //     // 当前 - 带箭头 -> 全局
        //     this.changeAge(age);
        //     this.changeName(name);
        // }

        fn();
    }


}

var user = new User('zhang', 30);
user.chage('long', 20);

console.log('chage修改后：', user);



//  函数 -es5
function calc(x, y) {
    return x * y;
}

console.log(calc(1, 5));

//  函数 -es6
var es6calc = (x, y) => {
    return x * y;
}

console.log(es6calc(1, 2));