Php 使用链接的多值解析xml

我有如下xml：

<?xml version="1.0" encoding="UTF-8"?>
<shop>
  <categories>
    <category id="310" parent_id="305" title="PHILIPS"/>
     <category id="305" parent_id="233" title="LED TV"/>
     <category id="233" parent_id="0" title="Television" title_ru="cat1 ru" title_en="cat1 en"/>

     <category id="525" parent_id="435" title="Manufacturer"/>
     <category id="396" parent_id="0" title="Parrent categgory"/>
     <category id="435" parent_id="396" title="Sub category"/>
  </categories>
  <products>
    <product id="807" category_id="525" code="1002" price="3.95" count="99" name="Product 1"/>
    <product id="2002" category_id="525" code="EFG 90750X" price="99" count="0" name="Product 2"/>
    <product id="2691" category_id="525" code="L 87695WD" price="99" count="1" name="Product 3"/>
    <product id="2909" category_id="525" code="ZEI 6240FBA" price="99" count="0" name="Product 4"/>
    <product id="3532" category_id="525" code="HK 654400XB" price="99" count="0" name="Product 5"/>
<product id="4150" category_id="310" code="24PHH4109/88" price="99" is_featured="1" count="&gt;10" name="Product 6"/>
    <product id="4378" category_id="310" code="22PFK4209/12" price="99" is_featured="1" count="&gt;10" name="Product 7"/>
    <product id="4065" category_id="310" code="22PFH4109/88" price="99" is_featured="1" count="&gt;10" name="Product 8"/>
    <product id="4080" category_id="310" code="20PHH4109/88" price="99" is_featured="1" count="&gt;10" name="Product 9"/>
  </products>
</shop>

---

但在这种情况下，我没有得到“制造商”、“平行类别”和“子类别”的值，如何解析它？

一种方法是对XML对象使用查询：

$url = "code.xml";
$xml = simplexml_load_file($url);

foreach ($xml->products->product as $product) {
    // Get categories
    $categoryId           = $product['category_id'];
    list($category)       = $xml->xpath("//category[@id=$categoryId]");

    $subCategoryId        = $category['parent_id'];
    list($subCategory)    = $xml->xpath("//category[@id=$subCategoryId]");

    $parentCategoryId     = $subCategory['parent_id'];
    list($parentCategory) = $xml->xpath("//category[@id=$parentCategoryId]");

    // Show categories
    echo "Category:        ", $category['title'], PHP_EOL;
    echo "Sub category:    ", $subCategory['title'], PHP_EOL;
    echo "Parent category: ", $parentCategory['title'], PHP_EOL;

    // Same as before
    echo
        '"L_'.$product[0]['code'].'_'.$product[0]['id'].
        '"^"'.$product[0]['name'].
        '"^"'.$product[0]['category_id'].
        '"^"0.01"^^^^^'
        .'"'.$product[0]['code'].'"'.
        "\n";
}

输出：

Category:        Manufacturer
Sub category:    Sub category
Parent category: Parrent categgory
"L_1002_807"^"Product 1"^"525"^"0.01"^^^^^"1002"
Category:        Manufacturer
Sub category:    Sub category
Parent category: Parrent categgory
"L_EFG 90750X_2002"^"Product 2"^"525"^"0.01"^^^^^"EFG 90750X"
...
Category:        PHILIPS
Sub category:    LED TV
Parent category: Television
"L_20PHH4109/88_4080"^"Product 9"^"310"^"0.01"^^^^^"20PHH4109/88"

---

XPath是一条出路。但是您需要将任务分开。为“编号”变量调用相同的代码（或使用多个前缀，如：

sub

，

parent

）是使用循环的好迹象

在本例中，循环获取类别数据，只要它获取的父id大于零

$dom = new DOMDocument();
$dom->loadXml($xml);
$xpath = new DOMXPath($dom);

function getCategories($xpath, $id) {
  $result = [];
  do {
    $categories = $xpath->evaluate('/shop/categories/category[@id = "'.$id.'"]'); 
    if ($category = $categories->item(0)) {
      $result[$id] = [
        'id' => $id,
        'title' => $category->getAttribute('title')
      ];
      $id = $category->getAttribute('parent_id');
    } else {
      break;
    }
  } while ($id > 0);
  return $result;
}

$result = [];
foreach ($xpath->evaluate('//product') as $product) {
  $result[] = [
    'name' => $product->getAttribute('name'),
    'categories' => getCategories($xpath, $product->getAttribute('category_id'))
  ];
}
var_dump($result);

输出：

array(9) {
  [0]=>
  array(2) {
    ["name"]=>
    string(9) "Product 1"
    ["categories"]=>
    array(3) {
      [525]=>
      array(2) {
        ["id"]=>
        string(3) "525"
        ["title"]=>
        string(12) "Manufacturer"
      }
      [435]=>
      array(2) {
        ["id"]=>
        string(3) "435"
        ["title"]=>
        string(12) "Sub category"
      }
      [396]=>
      array(2) {
        ["id"]=>
        string(3) "396"
        ["title"]=>
        string(17) "Parrent categgory"
      }
    }
  }
  [1]=>
  array(2) {
    ["name"]=>
    string(9) "Product 2"
    ["categories"]=>
    array(3) {
      [525]=>
      array(2) {
        ["id"]=>
        string(3) "525"
        ["title"]=>
        string(12) "Manufacturer"
      }
      ...

array(9) {
  [0]=>
  array(2) {
    ["name"]=>
    string(9) "Product 1"
    ["categories"]=>
    array(3) {
      [525]=>
      array(2) {
        ["id"]=>
        string(3) "525"
        ["title"]=>
        string(12) "Manufacturer"
      }
      [435]=>
      array(2) {
        ["id"]=>
        string(3) "435"
        ["title"]=>
        string(12) "Sub category"
      }
      [396]=>
      array(2) {
        ["id"]=>
        string(3) "396"
        ["title"]=>
        string(17) "Parrent categgory"
      }
    }
  }
  [1]=>
  array(2) {
    ["name"]=>
    string(9) "Product 2"
    ["categories"]=>
    array(3) {
      [525]=>
      array(2) {
        ["id"]=>
        string(3) "525"
        ["title"]=>
        string(12) "Manufacturer"
      }
      ...