使用PHP和XPath解析XML数据并动态渲染HTML表格教程

<?xml version="1.0"?>
<ArrayOfHighwayRoutingData xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <HighwayRoutingData>
    <tag>I80</tag>
    <destinationSymbols>
      <string>SFO</string>
      <string>OAK</string>
      <string>EMR</string>
      <string>ELC</string>
      <string>RIC</string>
      <string>SPB</string>
    </destinationSymbols>
  </HighwayRoutingData>
  <HighwayRoutingData>
    <tag>SR24</tag>
    <destinationSymbols>
      <string>OAK</string>
      <string>ORI</string>
      <string>LFY</string>
      <string>WCR</string>
    </destinationSymbols>
  </HighwayRoutingData>
  <HighwayRoutingData>
    <tag>US101</tag>
    <destinationSymbols>
      <string>SFO</string>
      <string>SSC</string>
      <string>MIL</string>
      <string>PAO</string>
    </destinationSymbols>
  </HighwayRoutingData>
</ArrayOfHighwayRoutingData>

// ... (加载XML文件)
foreach ($orders->xpath("//HighwayRoutingData") as $routingPoints){
    $tag=(string)$routingPoints->tag;
    echo "<tr><td>".$tag."</td></tr>";
    // 错误：这里再次从整个$orders对象中查找所有destinationSymbols
    // 导致无法正确关联，或者重复输出所有符号
    foreach($orders->xpath("//destinationSymbols") as $symbols){
        $string=(string)$symbols->string;
        echo "<tr><td>".$string."</td></tr>";
    }
}
// ...

<?php
$file = "RouteSymbol.xml"; // 假设XML文件名为RouteSymbol.xml

if (file_exists($file)) {
    // 加载XML文件。LIBXML_NOERROR和LIBXML_ERR_NONE用于抑制XML解析警告和错误。
    $orders = simplexml_load_file($file, "SimpleXMLElement", LIBXML_NOERROR | LIBXML_ERR_NONE);

    if ($orders === false) {
        die("Error: Cannot load XML file or XML is malformed.");
    }

    echo "<table border='1' style='width: 300px; border-collapse: collapse;'>";

    // 遍历所有HighwayRoutingData元素
    foreach ($orders->xpath(".//HighwayRoutingData") as $routingPoints){
        $tag = (string)$routingPoints->tag; // 获取当前HighwayRoutingData的tag

        // 输出公路标签，使用粗体显示，并占据一整行
        echo "<tr><td style='background-color: #f2f2f2; font-weight: bold; padding: 8px;'>{$tag}</td></tr>";

        // 在当前routingPoints（HighwayRoutingData）的上下文中，查找所有的destinationSymbols/string
        // 注意这里的XPath是 ".//destinationSymbols//string"，
        // "." 表示当前节点，确保查询仅限于当前的HighwayRoutingData元素内部。
        foreach($routingPoints->xpath(".//destinationSymbols//string") as $symbol){
            $x = (string)$symbol; // 获取目的地符号的字符串值
            // 输出目的地符号
            echo "<tr><td style='padding: 5px 8px;'>{$x}</td></tr>";
        }
    }
    echo "</table>";
} else {
    echo "Invalid request: XML file not found!";
}
?>

<table border='1' style='width: 300px; border-collapse: collapse;'>
    <tr><td style='background-color: #f2f2f2; font-weight: bold; padding: 8px;'>I80</td></tr>
    <tr><td style='padding: 5px 8px;'>SFO</td></tr>
    <tr><td style='padding: 5px 8px;'>OAK</td></tr>
    <tr><td style='padding: 5px 8px;'>EMR</td></tr>
    <tr><td style='padding: 5px 8px;'>ELC</td></tr>
    <tr><td style='padding: 5px 8px;'>RIC</td></tr>
    <tr><td style='padding: 5px 8px;'>SPB</td></tr>
    <tr><td style='background-color: #f2f2f2; font-weight: bold; padding: 8px;'>SR24</td></tr>
    <tr><td style='padding: 5px 8px;'>OAK</td></tr>
    <tr><td style='padding: 5px 8px;'>ORI</td></tr>
    <tr><td style='padding: 5px 8px;'>LFY</td></tr>
    <tr><td style='padding: 5px 8px;'>WCR</td></tr>
    <tr><td style='background-color: #f2f2f2; font-weight: bold; padding: 8px;'>US101</td></tr>
    <tr><td style='padding: 5px 8px;'>SFO</td></tr>
    <tr><td style='padding: 5px 8px;'>SSC</td></tr>
    <tr><td style='padding: 5px 8px;'>MIL</td></tr>
    <tr><td style='padding: 5px 8px;'>PAO</td></tr>
</table>

+-------+
| I80   |
+-------+
| SFO   |
+-------+
| OAK   |
+-------+
| EMR   |
+-------+
| ELC   |
+-------+
| RIC   |
+-------+
| SPB   |
+-------+
| SR24  |
+-------+
| OAK   |
+-------+
| ORI   |
+-------+
| LFY   |
+-------+
| WCR   |
+-------+
| US101 |
+-------+
| SFO   |
+-------+
| SSC   |
+-------+
| MIL   |
+-------+
| PAO   |
+-------+