So verketten Sie ähnliche Tags in einem XML

Hier ist eine Möglichkeit, das Problem zu lösen. Es werden keine Namen der untergeordneten Knoten hartcodiert (TI , MO , AU usw.), sodass Sie es möglicherweise für ähnliche Dokumente verwenden können. Ich habe Kommentare in den Code eingefügt, also lesen Sie sie bitte und fragen Sie nach, wenn Sie nicht verstehen, was der Code tut.

$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();

Ausgabe aus dem von Ihnen geposteten XML:

<?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>