PHP DOMDOCUMENT getNamedItem

Here I am echoing out class elements from a webpage that I require (= 'titre'), but how do I echo out their value? Can't seem to make it work.

$html = file_get_contents('http://www.spoofedwebpage.int/notice/search/wanted');
$dom = new DOMDocument;
$dom->loadHTML($html);
$dom->preserveWhiteSpace = false;
$divs = $dom->getElementsByTagName('div');  // Sample to get div element
$spans = $dom->getElementsByTagName('span');  // Sample to get div element


$i = 0;
while($span = $spans->item($i++))
{
    $class_node = $span->attributes->getNamedItem('class');
    if($class_node)
    {
        if($class_node->value == "titre")
        {   
        echo "Class is : " . $span->attributes->getNamedItem('class')->value . 
"<br>";
    }
}
}

Class attributes are a little special, because they are token lists (several class names seperated by whitespace), However I suggest you use Xpath to fetch the nodes:

$html = <<<'HTML'
  <div class="titre foo">abc</div>
  <span class="titre bar">def</span> 
  <div class="bar">hij</div>
HTML;

$dom = new DOMDocument;
$dom->loadHTML($html);
$dom->preserveWhiteSpace = false;
$xpath = new DOMXpath($dom);

$expression = '//*[(self::div or self::span) and contains(concat(" ", normalize-space(@class), " "), " titre ")]';

foreach ($xpath->evaluate($expression) as $node) {
  echo "Text is: ", $node->nodeValue, "
";
}

Output: https://eval.in/162248

Text is: abc
Text is: def

About the expression:

Select any element in the document ...

//*

... if it is a div or span ...

//*[(self::div or self::span)]

... and the class attribute contains a class name titre

//*[ (self::div or self::span) and contains(concat(" ", normalize-space(@class), " "), " titre ") ]

normalize-space() takes a string and converts all whitespace groups into single spaces. It strips whitespaces from the start and end of the string too. concat is used to add a single space to the start and the end of the normalized string. The result is a string of class names like SPACE CLASS_ONE SPACE CLASS_TWO SPACE. This allows it to look for a substring like SPACE CLASS_ONE SPACE.

btw Are you sure that you're looking for titre and not title?

HINT The original answer selected the class attributes, see the history if you're interested in it.