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id	challengeType	forumTopicId	title
587d7fae367417b2b2512be6	6	18265	渲染数据源的图像

Description

前几个挑战中表明，JSON 数组中的每个对象都包含一个imageLink键，其值为猫图像的 URL。当你遍历这些对象的时候，你可以使用imageLink属性在img元素中显示此图像。这是执行此操作的代码： html += "<img src = '" + val.imageLink + "' " + "alt='" + val.altText + "'>";

Instructions

添加代码以在img标签中使用imageLink和altText属性。

Tests

tests:
  - text: 你应该使用<code>imageLink</code>属性来显示图像。
    testString: assert(code.match(/val\.imageLink/g));
  - text: 应该用 <code>altText</code> 做为图片的 alt 属性。
    testString: assert(code.match(/val\.altText/g));

Challenge Seed

<script>
  document.addEventListener('DOMContentLoaded', function(){
    document.getElementById('getMessage').onclick = function(){
      const req=new XMLHttpRequest();
      req.open("GET",'/json/cats.json',true);
      req.send();
      req.onload = function(){
        const json = JSON.parse(req.responseText);
        let html = "";
        json.forEach(function(val) {
          html += "<div class = 'cat'>";
          // 在这行下面添加代码


          // 在这行上面添加代码
          html += "</div><br>";
        });
        document.getElementsByClassName('message')[0].innerHTML=html;
      };
     };
  });
</script>

<style>
  body {
    text-align: center;
    font-family: "Helvetica", sans-serif;
  }
  h1 {
    font-size: 2em;
    font-weight: bold;
  }
  .box {
    border-radius: 5px;
    background-color: #eee;
    padding: 20px 5px;
  }
  button {
    color: white;
    background-color: #4791d0;
    border-radius: 5px;
    border: 1px solid #4791d0;
    padding: 5px 10px 8px 10px;
  }
  button:hover {
    background-color: #0F5897;
    border: 1px solid #0F5897;
  }
</style>
<h1>Cat Photo Finder</h1>
<p class="message box">
  The message will go here
</p>
<p>
  <button id="getMessage">
    Get Message
  </button>
</p>

Solution

<script>
  document.addEventListener('DOMContentLoaded', function(){
    document.getElementById('getMessage').onclick = function(){
      const req = new XMLHttpRequest();
      req.open("GET",'/json/cats.json',true);
      req.send();
      req.onload = function(){
        const json = JSON.parse(req.responseText);
        let html = "";
        json.forEach(function(val) {
          html += "<div class = 'cat'>";
          // Add your code below this line
          html += "<img src = '" + val.imageLink + "' " + "alt='" + val.altText + "'>";
          // Add your code above this line
          html += "</div><br>";
        });
        document.getElementsByClassName('message')[0].innerHTML = html;
      };
     };
  });
</script>
<style>
  body {
    text-align: center;
    font-family: "Helvetica", sans-serif;
  }
  h1 {
    font-size: 2em;
    font-weight: bold;
  }
  .box {
    border-radius: 5px;
    background-color: #eee;
    padding: 20px 5px;
  }
  button {
    color: white;
    background-color: #4791d0;
    border-radius: 5px;
    border: 1px solid #4791d0;
    padding: 5px 10px 8px 10px;
  }
  button:hover {
    background-color: #0F5897;
    border: 1px solid #0F5897;
  }
</style>
<h1>Cat Photo Finder</h1>
<p class="message">
  The message will go here
</p>
<p>
  <button id="getMessage">
    Get Message
  </button>
</p>

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