<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
  <script src="vue.min.js"></script>
  <script src="vue-resource.min.js"></script>
</head>
<body>
  <div id="app">
    <button @click="btnGet">获取评论</button>

    <ul>
      <li v-for="item in comments">{{item.content}}</li>
    </ul>
  </div>

  <script>
    var v