Insert XML element on the same line of deleted element - php

Question

I have a php document that deletes an XML element (with child elements), based on the value of the attribute "id", and then creates a new element with the same child elements, but with different text added from a form input:
<?php
function ctr($myXML, $id) {
$xmlDoc = new DOMDocument();
$xmlDoc->load($myXML);
$xpath = new DOMXpath($xmlDoc);
$nodeList = $xpath->query('//noteboard[#id="'.$id.'"]');
if ($nodeList->length) {
$node = $nodeList->item(0);
$node->parentNode->removeChild($node);
}
$xmlDoc->save($myXML);
}
$xml = 'xml.xml'; // file
$to = $_POST['eAttr'];// the attribute value for "id"
ctr($xml,$to);
$target = "3";
$newline = "
<noteboard id='".$_POST['eId']."'>
<noteTitle>".$_POST['eTitle']."</noteTitle>
<noteMessage>".$_POST['eMessage']."</noteMessage>
<logo>".$_POST['eType']."</logo>
</noteboard>"; // HERE
$stats = file($xml, FILE_IGNORE_NEW_LINES);
$offset = array_search($target,$stats) +1;
array_splice($stats, $offset, 0, $newline);
file_put_contents($xml, join("\n", $stats));
?>
XML.xml
<note>
<noteboard id="title">
<noteTitle>Title Text Here</noteTitle>
<noteMessage>Text Here</noteMessage>
<logo>logo.jpg</logo>
</noteboard>
</note>
This works fine, but I would like it to put the new XML content on the line that the old element (the deleted) used to be on, instead of $target adding it to line 3. It is supposed to look like that the element is being 'edited', but it doesn't achieve this if it is on the wrong line.

Answer 1

The lines in an XML document are not exactly relevant, they are just formatting so that the document is easier to read (by a human). Think of it as a tree of nodes. Not only the elements are nodes but any content, like the XML declaration attributes and any text.
With that in mind you can think about your problem as replacing an element node.
First create the new noteCard element. This can be encapsulated into a function:
function createNote(DOMDocument $document, $id, array $data) {
$noteboard = $document->createElement('notecard');
$noteboard->setAttribute('id', $id);
$noteboard
->appendChild($document->createElement('noteTitle'))
->appendChild($document->createTextNode($data['title']));
$noteboard
->appendChild($document->createElement('noteMessage'))
->appendChild($document->createTextNode($data['text']));
$noteboard
->appendChild($document->createElement('logo'))
->appendChild($document->createTextNode($data['logo']));
return $noteboard;
}
Call the function to create the new notecard element node. I am using string literals here, you will have to replace that with the variables from you form.
$newNoteCard = createNote(
$document,
42,
[
'title' => 'New Title',
'text' => 'New Text',
'logo' => 'newlogo.svg',
]
);
Now that you have the new notecard, you can search the existing and replace it:
foreach($xpath->evaluate('//noteboard[#id=3][1]') as $noteboard) {
$noteboard->parentNode->replaceChild($newNoteCard, $noteboard);
}
Complete example:
$document = new DOMDocument();
$document->formatOutput = true;
$document->preserveWhiteSpace = false;
$document->loadXml($xml);
$xpath = new DOMXpath($document);
function createNote(DOMDocument $document, $id, array $data) {
$noteboard = $document->createElement('notecard');
$noteboard->setAttribute('id', $id);
$noteboard
->appendChild($document->createElement('noteTitle'))
->appendChild($document->createTextNode($data['title']));
$noteboard
->appendChild($document->createElement('noteMessage'))
->appendChild($document->createTextNode($data['text']));
$noteboard
->appendChild($document->createElement('logo'))
->appendChild($document->createTextNode($data['logo']));
return $noteboard;
}
$newNoteCard = createNote(
$document,
42,
[
'title' => 'New Title',
'text' => 'New Text',
'logo' => 'newlogo.svg',
]
);
foreach($xpath->evaluate('//noteboard[#id=3][1]') as $noteboard) {
$noteboard->parentNode->replaceChild($newNoteCard, $noteboard);
}
echo $document->saveXml();