PHP:检查XML节点是否存在属性

Question

我似乎无法想出这个.我有以下XML文件:

<?xml version="1.0" encoding="UTF-8"?>
<targets>
  <showcases>
    <building name="Big Blue" />
    <building name="Shiny Red" />
    <building name="Mellow Yellow" />
  </showcases>
</targets>

我需要能够测试<building>具有给定名称的节点是否存在.我在Google上看到的所有内容都告诉我要执行以下操作:

$xdoc->getElementsByTagName('building')->item(0)->getAttributeNode('name')

...但如果我理解正确,那不是只测试第一个<building>节点吗？ item(0)？我需要使用XQuery吗？

我很感激一些帮助!谢谢!

Answer 1

我建议如下(PHP使用ext/simplexml和XPath):

$name = 'Shiny Red';
$xml = simplexml_load_string('<?xml version="1.0" encoding="UTF-8"?>
<targets>
  <showcases>
    <building name="Big Blue" />
    <building name="Shiny Red" />
    <building name="Mellow Yellow" />
  </showcases>
</targets>');
$nodes = $xml->xpath(sprintf('/targets/showcases/building[@name="%s"]', $name);
if (!empty($nodes)) {
    printf('At least one building named "%s" found', $name);
} else {
    printf('No building named "%s" found', $name);
}