Updating XML node with PHP

Question

I've an XML file test.xml

<?xml version="1.0"?>
<info>
  <user>
    <name>
      <firstname>FirstName</firstname>
      <lastname>Last Name</lastname>
      <nameCoordinate>
        <xName>125</xName>
        <yName>20</yName>
      </nameCoordinate>
    </name>
  </user>
</info>

I'm trying to update the node xName & yName using PHP on a form submission. So, I've loaded the file using simplexml_load_file(). The PHP form action code is below

<?php 
    $xPostName = $_POST['xName'];
    $yPostName = $_POST['yName'];

    //load xml file to edit
        $xml = simplexml_load_file('test.xml');

    $xml->info->user->name->nameCoordinate->xName = $xPostName;
    $xml->info->user->name->nameCoordinate->yName = $yPostName;
    echo "done";
?>

I want to update the node values but the above code seems to be incorrect. Can anyone help me rectify it??

UPDATE: My question is somewhat similar to this Updating a XML file using PHP but here, I'm loading the XML from an external file and also I'm updating an element, not an attribute. That's where my confusion lies.

what is not working as expected? you don't have an error explained. — Samuel Herzog
– Samuel Herzog, Commented Jan 20, 2011 at 14:02

Josh Davis · Accepted Answer · 2011-01-20 14:29:06Z

37

You're not accessing the right node. In your example, $xml holds the root node <info/>. Here's a great tip: always name the variable that holds your XML document after its root node, it will prevent such confusion.

Also, as Ward Muylaert pointed out, you need to save the file.

Here's the corrected example:

// load the document
// the root node is <info/> so we load it into $info
$info = simplexml_load_file('test.xml');

// update
$info->user->name->nameCoordinate->xName = $xPostName;
$info->user->name->nameCoordinate->yName = $yPostName;

// save the updated document
$info->asXML('test.xml');

answered Jan 20, 2011 at 14:29

Josh Davis

28.8k5 gold badges54 silver badges67 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

swl1020 Over a year ago

What will happen if the xName or yName node doesn't already exist?

user906379 Over a year ago

What if you have several users with several yName and want to edit all of them at once? Any thoughts?

Ward Muylaert · Accepted Answer · 2011-01-20 14:32:11Z

3

You have to write the changes back to the file, use the asXML method of the SimpleXMLElement.

edited Jan 20, 2011 at 14:32

answered Jan 20, 2011 at 14:07

Ward Muylaert

5654 silver badges30 bronze badges

2 Comments

ptamzz Over a year ago

I believe that rewrites the whole tags. I want to update only specific nodes.

Ward Muylaert Over a year ago

It does, but short of writing half the XML interpreting logic in your own code to only write specific nodes, I believe that is as far as you'll get with SimpleXML.

Ruhith Udakara · Accepted Answer · 2019-12-27 12:47:47Z

2

try like this.

$xmlDoc = new \DOMDocument;
$xmlDoc->load('Books.xml');
$response = $xmlDoc->getElementsByTagName('Text');

foreach ($response as $node){
        $node->nodeValue = 'test';
    }
$xmlDoc->saveXML();

this might not the best answer but it worked for me.

answered Dec 27, 2019 at 12:47

Ruhith Udakara

2,4522 gold badges22 silver badges26 bronze badges

Collectives™ on Stack Overflow

Updating XML node with PHP

3 Answers 3

2 Comments

2 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related