How to add missing elements from from two arrays to first array

Question

I am currently using SimpleXML to reading an xml file to generate my first array. This array displays a list of images that are found in a directory and written to xml file.

This has worked for me in the past until I upload new photos to the same album. I like to know what one does to get a complete list of images that got uploaded to the end of that first array. Any suggestions?

XML File:

<album>
<image path="/albums/1/images/100_4124.jpg" />
<image path="/albums/1/images/100_4307.jpg" />
<image path="/albums/1/images/100_4335.jpg" />
</album>

SimpleXML to get array:

$xml = simplexml_load_file('/albums/1/photos.xml');
foreach ($xml->image as $image)  {
    echo '<li><img src="'.$image.'"></li>';
}

What I am getting for my results:

<li><img src="/albums/1/images/100_4124.jpg"></li>
<li><img src="/albums/1/images/100_4307.jpg"></li>
<li><img src="/albums/1/images/100_4335.jpg"></li>

Scanning the directory for all images:

if ($handle = @opendir('/albums/1/')) {
    $filenames = array();
    while (false !== ($file = readdir($handle))) {
        $ext = substr($file, strrpos($file, '.') + 1);
        if ($file != '.' && $file != '..') {
            $filenames[] = $file;
            $total++;
        }
    }
}
closedir($handle);

foreach ($filenames as $filename) {
    echo '<li><img src="'.$filename.'"></li>';
}

What I would like to get for results using both arrays:

<li><img src="/albums/1/images/100_4124.jpg"></li>
<li><img src="/albums/1/images/100_4307.jpg"></li>
<li><img src="/albums/1/images/100_4335.jpg"></li>    

<li><img src="/albums/1/images/100_9000.jpg"></li>
<li><img src="/albums/1/images/100_9001.jpg"></li>
<li><img src="/albums/1/images/100_9002.jpg"></li>

The last 3 images that are missing from xml file would be added it to the end of the list.

You know what Anon, that is the solution to the true problem. — Anurag
– Anurag, Commented Jan 17, 2010 at 21:59

anomareh · Accepted Answer · 2010-01-17 22:14:09Z

1

Perhaps this would work for you?

<?php

$images = array();

foreach ($xml->image as $image) {
    $images[] = $image;
}

foreach (array_diff($filenames, $images) as $image) {
    $images[] = $image;
}

foreach ($images as $image) {
    echo '<li><img src="' . $image . '" /></li>';
}

?>

This is assuming that $image from the $xml->image and $filename from your dir search are formatted the same. From what you've shown they are. If they aren't should be easy enough to run them through a quick regex to get them in a state where they are comparable.

Any who it looks like array_diff() is what you're looking for.

edited Jan 17, 2010 at 22:14

answered Jan 17, 2010 at 22:08

anomareh

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1 Comment

Tim Over a year ago

Beautiful, that worked like a charm and it was easy to implement with what I already had.. Thanks

catsby · Accepted Answer · 2010-01-17 22:08:05Z

1

If you get a full list of the file names in the directory you could use PHP in_array and search for it in an array of your paths

$paths = array();
foreach ($xml->image as $image) {
    $paths[] = $image['path'];
}
foreach ($filenames as $filename) {
    if (!in_array($filename, $paths) {
        $newImage = $xml->addChild('image');
        $newImage->addAttribute('path', $filename);
    }
}

//  save adjusted xml file, assuming you have permission
$xml->asXML('/albums/1/photos.xml');
foreach ($xml->image as $image)  {
    echo '<li><img src="'.$image.'"></li>';
}

answered Jan 17, 2010 at 22:08

catsby

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