使用Javascript选择嵌套元素

Question

如何选择嵌套元素

例如

我们有这样的事情（这是列表页上看起来LinkedIn搜索人员时等）

<li class="page-list">
      <ol>
            <li class="active">1</li>
            <li><button data-ember-action="" data-ember-action-6289="6289" data-is-animating-click="true">2</button></li>
            <li><button data-ember-action="" data-ember-action-6291="6291">3</button></li>
            <li><button data-ember-action="" data-ember-action-6293="6293">4</button></li>
            <li><button data-ember-action="" data-ember-action-6295="6295">5</button></li>
            <li><button data-ember-action="" data-ember-action-6297="6297">6</button></li>
            <li><button data-ember-action="" data-ember-action-6299="6299">7</button></li>
            <li><button data-ember-action="" data-ember-action-6301="6301">8</button></li>
            <li><button data-ember-action="" data-ember-action-6303="6303">9</button></li>
            <li><button data-ember-action="" data-ember-action-6305="6305">10</button></li>
      </ol>
    </li>

现在，就像这样，页面上有多个li元素，但只有一个元素带有<li class="page-list">

现在，从这个li我想点击/选择这个

<button data-ember-action="" data-ember-action-6291="6291">3</button>

它进一步嵌套在<li>

[问题]有人可以帮助我，告诉我如何选择/点击这个？ 另外我不能使用data-ember-action因为在data-ember-action-6289中，6289不是固定的和随机的（对于不同的搜索可能不同），因此当我创建一个脚本来执行操作时，它不会了解data-ember-action中的数字。

Answer 1

一个简单的querySelector会这样做：

 console.log(document.querySelector('[data-ember-action-6291="6291"]')) 

 <li class="page-list"> <ol> <li class="active">1</li> <li><button data-ember-action="" data-ember-action-6289="6289" data-is-animating-click="true">2</button></li> <li><button data-ember-action="" data-ember-action-6291="6291">3</button></li> <li><button data-ember-action="" data-ember-action-6293="6293">4</button></li> <li><button data-ember-action="" data-ember-action-6295="6295">5</button></li> <li><button data-ember-action="" data-ember-action-6297="6297">6</button></li> <li><button data-ember-action="" data-ember-action-6299="6299">7</button></li> <li><button data-ember-action="" data-ember-action-6301="6301">8</button></li> <li><button data-ember-action="" data-ember-action-6303="6303">9</button></li> <li><button data-ember-action="" data-ember-action-6305="6305">10</button></li> </ol> </li> 

如果您不能指望data-属性，那么只需选择ol的第三个子项：

 console.log( document.querySelector('.page-list li:nth-child(3)') ); 

 <li class="page-list"> <ol> <li class="active">1</li> <li><button data-ember-action="" data-ember-action-6289="6289" data-is-animating-click="true">2</button></li> <li><button data-ember-action="" data-ember-action-6291="6291">3</button></li> <li><button data-ember-action="" data-ember-action-6293="6293">4</button></li> <li><button data-ember-action="" data-ember-action-6295="6295">5</button></li> <li><button data-ember-action="" data-ember-action-6297="6297">6</button></li> <li><button data-ember-action="" data-ember-action-6299="6299">7</button></li> <li><button data-ember-action="" data-ember-action-6301="6301">8</button></li> <li><button data-ember-action="" data-ember-action-6303="6303">9</button></li> <li><button data-ember-action="" data-ember-action-6305="6305">10</button></li> </ol> </li>