Comment concaténer des balises similaires dans un XML

Voici une façon de résoudre le problème. Il ne code en dur aucun des noms de nœuds enfants (TI , MO , AU , etc.) afin que vous puissiez éventuellement l'utiliser sur des documents similaires. J'ai mis des commentaires dans le code, veuillez donc les lire et demander si vous ne comprenez pas ce que fait le code.

$txt = 'your XML string goes here';
$dom = new DOMDocument;
$dom->preserveWhiteSpace = false;
$dom->formatOutput = true;
$dom->loadXML($txt);

$xp = new DOMXPath($dom);

# find all the nodes types that appear under Record
$cnode_type = array();
foreach ($xp->query("/Results/Recordset/Record/*") as $c) {
    $cnode_type[] = $c->nodeName;
}
# cnode_type now contains the different child node types
$cnode_type = array_unique($cnode_type);

# get all the Record nodes
$recs = $xp->query("/Results/Recordset/Record");

# for every Record node...
foreach ($recs as $par) {
    # for each type of child node...
    foreach ($cnode_type as $c) {
        # run an XPath query to count the number of children of node type $c
        # if there are more than one, we need to remove the extras
        if ($xp->evaluate("count($c)", $par) > 1) {
            # go through all the $c nodes, saving the value in $node_vals
            # delete the node
            $node_vals = [];
            foreach ($xp->query($c, $par) as $n) {
                # only save the contents of nodes with a value
                if (isset($n->nodeValue) && strlen($n->nodeValue) > 0) {
                    $node_vals[] = $n->nodeValue;
                }
                $par->removeChild($n);
            }
            # create a new $c node and set the value to the list in $node_vals
            # add it to the parent node
            $new_node = $dom->createElement($c, implode("; ", $node_vals));
            $par->appendChild($new_node);
        }
    }
}
# print out the result
echo $dom->saveXML();

Sortie du XML que vous avez posté :

<?xml version="1.0"?>
<Results>
  <Recordset setCount="3">
    <Record setEntry="0">
      <TI>Test-1</TI>
      <MO>Mo-1</MO>
      <JF>OK</JF>
      <JT/>
      <AU>One; Two; three</AU>
    </Record>
    <Record setEntry="1">
      <TI>Test-2</TI>
      <MO>Mo-2</MO>
      <JF/>
      <JT/>
      <AU>One; Two; Three; Four; Five; Six; Seven</AU>
    </Record>
    <Record setEntry="2">
      <TI>Test31</TI>
      <MO>Mo-3</MO>
      <JF/>
      <JT/>
      <AU>One</AU>
    </Record>
  </Recordset>
</Results>