<!DOCTYPE html> <html> <body> <h1>NodeList 对象</h1> <h2>length 属性</h2> <!-- 这是注释节点! --> <p>body 元素中的子节点数为:</p> <p id="demo"></p> <p>元素之间的空白是文本节点。注释也是节点。</p> <script> const nodeList = document.body.childNodes; let number = nodeList.length; document.getElementById("demo").innerHTML = number; </script> </body> </html>