Question

我是php新手。作为实习生，我必须使用XML文件中的数据填充MySQL中的数据库。问题是那些XML文件并不总是具有相同的格式。所以，我在php5中编写代码，我想知道如何计算特定子项在标记中出现的次数。在我的XML文件中，我想计算子节点“ing”出现在节点“ing-div”中的时间。某些XML文件可以包含一个，两个或更多“ing-div”节点。任何帮助？

这是XML文件

<?xml version="1.0" encoding="UTF-8" ?> 
- <recipeml version="0.5">
- <recipe>
- <head>
  <title>100 Whole Wheat Bread for Bread Machine</title> 
- <categories>
  <cat>Breadmaker</cat> 
  <cat>Breads</cat> 
  </categories>
  <yield>8</yield> 
  </head>
- <ingredients>
- <ing-div>
  <title>REGULAR LOAF</title> 
- <ing>
- <amt>
  <qty>1</qty> 
  <unit>cup</unit> 
  </amt>
  <item>Water</item> 
  </ing>
- <ing>
- <amt>
  <qty>2 1/2</qty> 
  <unit>cups</unit> 
  </amt>
  <item>Wheat bread flour</item> 
  </ing>
- <ing>
- <amt>
  <qty>1 1/4</qty> 
  <unit>tablespoons</unit> 
  </amt>
  <item>Dry milk</item> 
  </ing>
- <ing>
- <amt>
  <qty>1</qty> 
  <unit>teaspoon</unit> 
  </amt>
  <item>Salt</item> 
  </ing>
- <ing>
- <amt>
  <qty>1 1/2</qty> 
  <unit>tablespoons</unit> 
  </amt>
  <item>Butter</item> 
  </ing>
- <ing>
- <amt>
  <qty>1 1/4</qty> 
  <unit>tablespoons</unit> 
  </amt>
  <item>Honey</item> 
  </ing>
- <ing>
- <amt>
  <qty>1</qty> 
  <unit>tablespoon</unit> 
  </amt>
  <item>Gluten</item> 
  </ing>
- <ing>
- <amt>
  <qty>2</qty> 
  <unit>teaspoons</unit> 
  </amt>
  <item>Molasses</item> 
  </ing>
- <ing>
- <amt>
  <qty>1 1/2</qty> 
  <unit>teaspoons</unit> 
  </amt>
  <item>Fast-Rise yeast *** OR ***</item> 
  </ing>
- <ing>
- <amt>
  <qty>2</qty> 
  <unit>teaspoons</unit> 
  </amt>
  <item>Active-Dry yeast</item> 
  </ing>
  </ing-div>
- <ing-div>
  <title>LARGE LOAF</title> 
- <ing>
- <amt>
  <qty>1 1/2</qty> 
  <unit>cups</unit> 
  </amt>
  <item>+ 2 tb Water</item> 
  </ing>
- <ing>
- <amt>
  <qty>3 3/4</qty> 
  <unit>cups</unit> 
  </amt>
  <item>Wheat bread flour</item> 
  </ing>
- <ing>
- <amt>
  <qty>2</qty> 
  <unit>tablespoons</unit> 
  </amt>
  <item>Dry milk</item> 
  </ing>
- <ing>
- <amt>
  <qty>1 1/2</qty> 
  <unit>teaspoons</unit> 
  </amt>
  <item>Salt</item> 
  </ing>
- <ing>
- <amt>
  <qty>2</qty> 
  <unit>tablespoons</unit> 
  </amt>
  <item>Butter</item> 
  </ing>
- <ing>
- <amt>
  <qty>2</qty> 
  <unit>tablespoons</unit> 
  </amt>
  <item>Honey</item> 
  </ing>
- <ing>
- <amt>
  <qty>1 1/2</qty> 
  <unit>tablespoons</unit> 
  </amt>
  <item>Gluten</item> 
  </ing>
- <ing>
- <amt>
  <qty>1</qty> 
  <unit>tablespoon</unit> 
  </amt>
  <item>Molasses</item> 
  </ing>
- <ing>
- <amt>
  <qty>2 1/8</qty> 
  <unit>teaspoons</unit> 
  </amt>
  <item>Fast-Rise yeast *** OR ***</item> 
  </ing>
- <ing>
- <amt>
  <qty>3</qty> 
  <unit>teaspoons</unit> 
  </amt>
  <item>Active-Dry yeast</item> 
  </ing>
  </ing-div>
  </ingredients>
- <directions>
  <step>The trick to making 100% whole wheat bread in your machine is an extra knead, which gives the yeast and gluten a second chance to create a lighter loaf. When your first knead cycle is completed, simply reset the machine and start again. Some manufacturers produce home bakeries with a whole wheat cycle; if your machine doesn't have one, this start- again method works as an easy alternative. SUCCESS HINTS: The gluten gives the whole wheat flour the structure necessary for a good loaf. If your market doesn't stock wheat gluten, try your local health food store. Remember the extra knead. It's especially important in 100% whole wheat bread. Because of the extra knead, us this recipe only on the regular bake cycle. CALORIES: 125 PROTEIN: 14% CHOLESTEROL: 3.98mg CARBOHYDRATES: 73% SODIUM: 218mg FAT: 13% Posted to Bakery-Shoppe Digest V1 #410 by serge.cyr@sympatico.ca (Serge Cyr) on Nov 23, 1997</step> 
  </directions>
  </recipe>
  </recipeml>

这是代码的一部分，我试图计算“ing-div”中“ing”的出现次数

$xml = simplexml_load_file($file);
$ing_elem = new SimpleXMLElement($xml);
printf("%d ing.\n", $ing_elem->{'ing-div'}->count() );

但是，它根本不起作用。我有错误消息：

致命错误：在第115行的C：\ wamp \ www \ PhP \ Folder xml \ New_Load_All_Files_1.php中显示消息'字符串无法解析为XML'的未捕获异常'异常'

anny建议？

非常感谢您的时间和帮助。

T3000

Answer 1

$xml = new DOMDocument();
$xml->load(path/to/file);
$xpath = new DOMXPath($xml);
$ingdiv = $xpath->query("/recipeml/recipe/ingredients/ing-div");
$length = $ingdiv->length;
// iterate over all <ing-div> from last to first
while($length--)
{
    // number of <ing> in the specific <ing-div>
    print $xpath->query("ing", $ingdiv->item($length))->length;
}

编辑：

你不应该复制＆amp;从浏览器粘贴格式化的输出。

<?xml version="1.0" encoding="UTF-8" ?>
- <recipeml/>

这是格式错误的XML。 XML不能在根节点之外有文本。

Answer 2

我认为您不需要以下内容：

$ing_elem = new SimpleXMLElement($xml);

因为您使用simplexml_load_file（$ file）来创建SimpleXMLElement对象

因此，只能使用以下行创建simpleXML对象：

$ing_elem = simplexml_load_file($file);

您可以使用以下代码片段来获取有关可能发生的错误的更多信息：

libxml_use_internal_errors(true);
$ing_elem = simplexml_load_file($file);
if (!$ing_elem) {
    echo "Failed loading XML\n";
    foreach(libxml_get_errors() as $error) {
        echo "\t", $error->message;
    }
}

如何计算标签中孩子的出现次数？

2 个答案: