如何遍历远程XML文件并生成含所有唯一标签的PHP数组

需求说明 #

需要从远程XML文件生成一个包含所有唯一标签名的PHP数组，由于XML的深度和结构未知，递归函数是最佳实现方式。

现有代码 #

$xml = file_get_contents('https://sxy.bg/test.xml');
$xml = simplexml_load_string($xml, 'SimpleXMLElement', LIBXML_NOCDATA);

目标XML内容 #

<rss version="2.0">
<channel>
<title name="product">Test Store</title>
<link type="url">https://www.sxy.bg/</link>
<description encoding="utf-8">SXY</description>
<item>
<g:id>8797</g:id>
<g:title>Product Title 8797</g:title>
<g:description>Product description 8797</g:description>
<g:link>https://www.sxy.bg/store/8797</g:link>
<g:image_link>https://www.sxy.bg/images/store/8797.jpg</g:image_link>
<g:brand>Olight</g:brand>
<g:condition>new</g:condition>
<g:availability>in stock</g:availability>
<g:price>99.00 EUR</g:price>
<g:shipping>
<g:country>BG</g:country>
<g:service>Standard</g:service>
<g:price>4.95 EUR</g:price>
</g:shipping>
<g:google_product_category>Auto</g:google_product_category>
<g:custom_label_0>Hot Offers</g:custom_label_0>
</item>
<item>
<g:id>8813</g:id>
<g:title>Product Title 8813</g:title>
<g:description>Product description 8813</g:description>
<g:link>https://www.sxy.bg/store/8813</g:link>
<g:image_link>https://www.sxy.bg/images/store/8813.jpg</g:image_link>
<g:brand>Olight</g:brand>
<g:condition>new</g:condition>
<g:availability>in stock</g:availability>
<g:price>305.00 EUR</g:price>
<g:shipping>
<g:country>BG</g:country>
<g:service>Standard</g:service>
<g:price>4.95 EUR</g:price>
</g:shipping>
<g:google_product_category>Auto</g:google_product_category>
<g:custom_label_0>Hot Offers</g:custom_label_0>
</item>
<item>
<g:id>8809</g:id>
<g:title>Product Title 8809</g:title>
<g:description>Product description 8809</g:description>
<g:link>https://www.sxy.bg/store/8809</g:link>
<g:image_link>https://www.sxy.bg/images/store/8809.jpg</g:image_link>
<g:brand>Olight</g:brand>
<g:condition>new</g:condition>
<g:availability>in stock</g:availability>
<g:price>375.00 EUR</g:price>
<g:shipping>
<g:country>BG</g:country>
<g:service>Standard</g:service>
<g:price>4.95 EUR</g:price>
</g:shipping>
<g:google_product_category>Auto</g:google_product_category>
<g:custom_label_0>Hot Offers</g:custom_label_0>
</item>
</channel>
</rss>

期望输出数组 #

array("channel", "title", "link", "description", "item", "g:id", "g:title", "g:description", "g:link", "g:image_link", "g:brand", "g:condition", "g:availability", "g:price", "g:shipping", "g:country", "g:service", "g:google_product_category", "g:custom_label_0");

解决方案 #

实现思路 #

1. 编写递归函数遍历所有SimpleXMLElement节点，收集每个节点的标签名（含命名空间前缀）
2. 使用数组去重函数确保标签唯一
3. 整理结果为目标格式

完整代码实现 #

// 获取远程XML内容并解析
$xmlContent = file_get_contents('https://sxy.bg/test.xml');
$xml = simplexml_load_string($xmlContent, 'SimpleXMLElement', LIBXML_NOCDATA);

// 递归收集标签名的函数
function collectTags($node, &$tags) {
    // 获取当前节点的标签名（含命名空间）
    $tagName = $node->getName();
    $tags[] = $tagName;
    
    // 遍历所有子节点，递归处理
    foreach ($node->children() as $child) {
        collectTags($child, $tags);
    }
}

// 初始化标签数组
$tags = [];
// 从根节点开始遍历
collectTags($xml, $tags);

// 去重并重置数组索引
$uniqueTags = array_values(array_unique($tags));

// 输出结果（或按需使用）
print_r($uniqueTags);

代码说明 #

• collectTags函数通过递归遍历每个节点，将标签名存入引用传递的数组中
• array_unique用于去除重复的标签名
• array_values重置数组索引，确保输出为连续的数字索引数组

执行上述代码后，将得到与期望格式一致的唯一标签数组。

内容的提问来源于stack exchange，提问作者Europeuser