ES6 简单笔记2

26. ES6 Promise 简介

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
    <script>

        // 无法请求谁先谁后
        // let user;
        // $.get('https://api.github.com/users',data=>{
        //     console.log('fetched all user');
        //     user=data[0].login;
        // })

        // $.get(`https://api.github.com/users/${user}/repos`,data=>{
        //     console.log('fetched user repos');
        //     console.log(data);
        // })


        // 为了确保顺序就会把第二个请求放到第一个
        // let user;
        // $.get('https://api.github.com/users',data=>{
        //     console.log('fetched all user');
        //     user=data[0].login;

        //     $.get(`https://api.github.com/users/${user}/repos`,data=>{
        //         console.log('fetched user repos');
        //         console.log(data);
        //     })
        // })




        // 为了避免回调地狱，解决方案使用Promise，不管如何都会返回一个结果
       



    </script>
</body>
</html>

axios

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script> -->
    <script src="https://cdnjs.cloudflare.com/ajax/libs/axios/0.16.2/axios.min.js"></script>
    <script>
        // 为了避免回调地狱，解决方案使用Promise，不管如何都会返回一个结果

        let username;
        // 这里返回一个Promise
       const users= axios.get('https://api.github.com/users');
        

       //then相当jquery的监听事件
       users.then(response=>{
        username = response.data[0].login;
        return axios.get(`https://api.github.com/users/${username}/repos`);
       }).then(reponse=>{
        console.log(reponse.data);
       }).catch(err=>{
            console.log(err);
       })


    </script>
</body>
</html>