PHP SimpleXML Group By Element Type

问题:

Ok here's my dilemma. I am looking for a way to consolidate the data in a group using SimpleXML in PHP. Here's what I mean.

Let's say I have an xml that looks like this:

  <favorites>
    <interesting>
        <type>Movie</type>
        <character>James Bond</character>
        <name>Casino Royale</name>
    </interesting>
    <interesting>
        <type>Movie</type>
        <character>Jason Bourne</character>
        <name>Bourne Identity</name>
    </interesting>
    <interesting>
        <type>Book</type>
        <character>Lindsay Ford</character>
        <name>Shantaram</name>
    </interesting>
  </favorites>

Now here's what I want that to look like:

Movie

• Casino Royale - James Bond Bourne
• Bourne Identity - Jason Bourne

Book

• Shantaram - Lindsay Ford

Please help me!! Let me know if anything is confusing.

回答1:

If you don't know in advance the types of movies, you could :

• extract all types from the XML data
  • get them as unique, as they may appear several times (There might be a way to do that with XPath ; I don't know it, so I'll use array_unique)
• iterate over these types, using what @Mark proposed.

Something like this would probably do :

$xml = simplexml_load_string($xmlData);

$typesListXml = $xml->xpath('interesting/type');
var_dump($typesListXml);    // var_dump #1

if (!empty($typesListXml)) {
    $typesList = array();
    foreach ($typesListXml as $typeXml) {
        $typesList[] = (string)$typeXml;
    }
    var_dump($typesList);    // var_dump #2

    $typesList = array_unique($typesList);
    var_dump($typesList); // var_dump #3

    $moviesForType = array();
    foreach ($typesList as $type) {
        $rawData = $xml->xpath('interesting[type="' . $type . '"]');
        if (!empty($rawData)) {
            foreach ($rawData as $rawMovie) {
                $moviesForType[$type][] = $rawMovie->name . ' - ' . $rawMovie->character;
            }
        }
    }

    var_dump($moviesForType); // var_dump #4

    // Up to you to present $moviesForType the way you want ;-)

}

And to make things easier to understand, here are the var_dump's outputs :

var_dump #1 :

array
  0 => 
    object(SimpleXMLElement)[2]
      string 'Movie' (length=5)
  1 => 
    object(SimpleXMLElement)[3]
      string 'Movie' (length=5)
  2 => 
    object(SimpleXMLElement)[4]
      string 'Book' (length=4)

var_dump #2 :

array
  0 => string 'Movie' (length=5)
  1 => string 'Movie' (length=5)
  2 => string 'Book' (length=4)

var_dump #3 :

array
  0 => string 'Movie' (length=5)
  2 => string 'Book' (length=4)

var_dump #3 :

array
  'Movie' => 
    array
      0 => string 'Casino Royale - James Bond' (length=26)
      1 => string 'Bourne Identity - Jason Bourne' (length=30)
  'Book' => 
    array
      0 => string 'Shantaram - Lindsay Ford' (length=24)

Now, it's up to you to present those data the way you want ; a double-foreach loop constructing <ul> and <li> tags would probably do ;-)

回答2:

I believe you are looking for Xpath:

$xmlData = '<favorites>...</favorites>';
$xml = simplexml_load_string($xmlData);
$arrMovies = $xml->xpath('interesting[type="Movie"]');
$arrBooks = $xml->xpath('interesting[type="Book"]');

You can then loop over $arrMovies and $arrBooks and print out what you need:

foreach($arrMovies as $movie) {
    echo $movie->name;
}