PHP script to echo VLC now playing XML attributes

Question

I\'ve been searching for a while on this and haven\'t had much luck. I\'ve found plenty of resources showing how to echo data from dynamic XML, but I\'m a PHP novice, and nothi

Answer 1

Instead of using a for loop, you can obtain the same result with XPath:

// Extraction splitted across two lines for clarity
$artist_xpath = $sxe->xpath('//info[@name="artist"]');
$artist = (string) $artist_xpath[0];
echo $artist;

You will have to adjust the xpath expression (i.e. change @name=... appropriately), but you get the idea. Also notice that [0] is necessary because xpath will return an array of matches (and you only need the first) and the cast (string) is used to extract text contained in the node.

Besides, your XML is invalid and will be rejected by the parser because of the literal & appearing in the <info name="album"> tag.

Answer 2

If you look at your code again, you are missing a function that turns the first result of the xpath expression into a string of a SimpleXMLElement (casting).

One way to write this once is to extend from SimpleXMLElement:

class BetterXMLElement extends SimpleXMLElement
{
    public function xpathString($expression) {
        list($result) = $this->xpath($expression);
        return (string) $result;
    }
}

You then create the more specific SimpleXMLElement like you did use the less specific before:

$file = file_get_contents('http://192.168.0.15:8080/requests/status.xml');
$sxe  = new BetterXMLElement($file);

And then you benefit in your following code:

$artist = $sxe->xpathString('//info[@name="artist"]');
$album  = $sxe->xpathString('//info[@name="album"]');
$title  = $sxe->xpathString('//info[@name="title"]');

echo "<B>Artist: </B>".$artist."</br>";
echo "<B>Title: </B>".$title."</br>";
echo "<B>Album: </B>".$album."</br>";

This spares you some repeated code. This means as well less places you can make an error in :)

Sure you can further on optimize this by allowing to pass an array of multiple xpath queries and returning all values named then. But that is something you need to write your own according to your specific needs. So use what you learn in programming to make programming more easy :)

If you want some more suggestions, here is another, very detailed example using DOMDocument, the sister-library of SimpleXML. It is quite advanced but might give you some good inspiration, I think something similar is possible with SimpleXML as well and this is probably what you're looking for in the end:

• Extracting data from HTML using PHP and xPath