您好，我是编码的新手，有一个一般性的问题，我四处张望，找不到解决方案。我正在关注一个JavaScript教程，并遇到了这一特定的代码行。子节点指出属性“ backgroundColor”是未定义的，我不确定为什么。
错误：“未捕获的typeerror：无法设置未定义的属性'backgroundColor'”
<!doctype html>
<html>
<head>
</head>
<body>
<div id = "sampDiv">
<p> This is a txt field </p>
<p> This is another txt field </p>
</div>
<script>
var sampDiv = document.getElementById("sampDiv");
sampDiv.childNodes[0].style.backgroundColor = "red";
</script>
</body>
</html>
最佳答案
使用children[0]代替childNodes[0]：
https://developer.mozilla.org/en-US/docs/Web/API/ParentNode/children
var sampDiv = document.getElementById("sampDiv");
sampDiv.children[0].style.backgroundColor = "red";<!doctype html>
<html>
<head>
</head>
<body>
<div id = "sampDiv">
<p> This is a txt field </p>
<p> This is another txt field </p>
</div>
</body>
</html>