php - 使用 : 读取 XML 节点

Question

我有一个供稿，但有一个 :在我要检索的 who's 值的项目中。我该怎么办？

饲料:http://publishers.spilgames.com/rss?lang=en-US&tsize=1&format=xml&limit=100

foreach($xml->entry as $game) {     
    $it = $it+1;
    $name = mysql_real_escape_string($game->title);         
    $link = $game->link[href];
    $description = mysql_real_escape_string($game->media:description);  

Answer 1

这就是所谓的 xml 命名空间的前缀。 See this namespace tutorial .

您实际上并不匹配前缀，而是匹配前缀所代表的命名空间。

您如何执行此操作完全取决于您用于操作 xml 的内容。你没有说你在使用什么，但我猜你正在使用 SimpleXML。

使用 SimpleXML，默认情况下，对象访问树中只包含没有命名空间的节点。要获取命名空间元素，您需要明确要求它们:

$xml=simplexml_load_file('http://publishers.spilgames.com/rss?lang=en-US&tsize=1&format=xml&limit=100');

foreach($xml->entry as $game) {
    $description = (string) $game->children('http://search.yahoo.com/mrss/')->description;
    var_dump($description);
}

尽管在这种特殊情况下它可能不是最佳选择，但您也可以使用 XPath 更直接地匹配命名空间节点:

$xml=simplexml_load_file('http://publishers.spilgames.com/rss?lang=en-US&tsize=1&format=xml&limit=100');

$NS = array(
    'media' => 'http://search.yahoo.com/mrss/',
);
foreach ($NS as $prefix => $uri) {
    $xml->registerXPathNamespace($prefix, $uri);
}

foreach($xml->entry as $entry) {
    // match the first media:description element
    // get the first SimpleXMLElement in the match array with current()
    // then coerce to string.
    $description = (string) current($entry->xpath('media:description[1]'));
    var_dump($description);
}

这是一个更完整的示例，它也稍微修饰了您的代码。

$xml=simplexml_load_file('http://publishers.spilgames.com/rss?lang=en-US&tsize=1&format=xml&limit=100');

// This gets all the namespaces declared in the root element
// using the prefix as declared in the document, for convenience.
// Note that prefixes are arbitrary! So unless you're confident they
// won't change you should not use this shortcut
$NS = $xml->getDocNamespaces();

$games = array();
foreach($xml->entry as $entry) {
    $mediaentry = $entry->children($NS['media']);
    $games[] = array(
        // to get the text value of an element in SimpleXML, you need
        // explicit cast to string
        'name' => (string) $entry->title,
        // DO NOT EVER use array-access brackets [] without quoting the string in them!
        // I.e., don't do "$array[name]", do "$array['name']"
        // This is a PHP error that happens to work.
        // PHP looks for a *CONSTANT* named HREF, and replaces it with
        // string 'href' if it doesn't find one. This means your code will break
        // if define('href') is ever used!!
        'link' => (string) $entry->link['href'],
        'description' => (string) $mediaentry->description,
    );
}
$it = count($games); // there is no need for your $it+1 counter!

// $games now has all your data.
// If you want to insert into a database, use PDO if possible and prepare a query
// so you don't need a separate escaping step.
// If you can't use PDO then do:
// $escapedgame = array_map('mysql_real_escape_string', $thegame);