<html>
    <head>
        <meta charset=utf-8>
    </head>
    <body>
        <ul>
            <li>nowcoder</li>
        </ul>
    </body>
    <script type="text/javascript">
        // 补全代码
        var li=document.querySelector('li')
        li.addEventListener('click',e=>{//addEventListener() 方法用于向指定元素添加监听事件
            e.stopPropagation() // event.stopPropagation() 阻止捕获和冒泡阶段中当前事件的进一步传播               
        })
    </script>
</html>