Question

我有一个输入字段，其中包含以下文本：

<?xml version="1.0" encoding="utf-8"?>
<players timestamp="1536505850">
  <player id="0518" name="Eagles, Philadelphia" position="Def" team="PHI" />
  <player id="10271" name="Jones, Julio" position="WR" team="ATL" />
  <player id="12154" name="Ajayi, Jay" position="RB" team="PHI" />
</players>

我有这些变量：

var outputField = document.getElementById('output');
var parser = new DOMParser();
var xmlDoc = parser.parseFromString(document.getElementById('output'), "text/xml");

当我这样称呼时：

xmlDoc.getElementsByTagName("player")[0].childNodes[0].nodeValue;

我收到此错误：

未捕获的TypeError：无法读取在1：1：41处未定义的属性'childNodes'

我在做什么错了？

Answer 1

player 元素没有子节点。您需要缩短产生

错误的行

xmlDoc.getElementsByTagName("player")[0].childNodes[0].nodeValue;

到

xmlDoc.getElementsByTagName("player")[0].nodeValue;

最好知道您要访问的内容，因为上面的语句的评估结果为null：

var outputField = document.getElementById('output');

var parser = new DOMParser();
var xmlDoc = parser.parseFromString(outputField.value, "text/xml");

console.log(xmlDoc.getElementsByTagName("player")[0].nodeValue);

<html>
<body>
<textarea id="output">
<?xml version="1.0" encoding="utf-8"?>
<players timestamp="1536505850">
  <player id="0518" name="Eagles, Philadelphia" position="Def" team="PHI" />
  <player id="10271" name="Jones, Julio" position="WR" team="ATL" />
  <player id="12154" name="Ajayi, Jay" position="RB" team="PHI" />
</players>
</textarea>
</body>
</html>

更新：下面是一个如何从“玩家”元素获取属性的示例：

var outputField = document.getElementById('output');

var parser = new DOMParser();
var xmlDoc = parser.parseFromString(outputField.value, "text/xml");

console.log(xmlDoc.getElementsByTagName("player")[0].getAttribute('name'));

<html>
<body>
<textarea id="output">
<?xml version="1.0" encoding="utf-8"?>
<players timestamp="1536505850">
  <player id="0518" name="Eagles, Philadelphia" position="Def" team="PHI" />
  <player id="10271" name="Jones, Julio" position="WR" team="ATL" />
  <player id="12154" name="Ajayi, Jay" position="RB" team="PHI" />
</players>
</textarea>
</body>
</html>

我似乎无法正确解析JS中的XML数据

1 个答案: