Get last modified file in a directory

I don't remember having ever seen a function that would do what you ask.

So, I think you will have to go through all (at least jpg/png/gif) files, and search for the last modification date of each of them.

Here's a possible solution, based on the DirectoryIterator class of the SPL :

$path = null;
$timestamp = null;

$dirname = dirname(__FILE__);
$dir = new DirectoryIterator($dirname);
foreach ($dir as $fileinfo) {
    if (!$fileinfo->isDot()) {
        if ($fileinfo->getMTime() > $timestamp) {
            // current file has been modified more recently
            // than any other file we've checked until now
            $path = $fileinfo->getFilename();
            $timestamp = $fileinfo->getMTime();
        }
    }
}

var_dump($path);

Of course, you could also do the same thing with readdir() and other corresponding functions.

function listdirfile_by_date($path)
{
    $dir = opendir($path);
    $list = array();
    while($file = readdir($dir))
    {
        if($file != '..' && $file != '.')
        {
            $mtime = filemtime($path . $file) . ',' . $file;
            $list[$mtime] = $file;
        }
    }
    closedir($dir);
    krsort($list);

    foreach($list as $key => $value)
    {
        return $list[$key];
    }
    return '';
}

Yes you have to read through them all. But since directory accesses are cached, you shouldn't really worry about it.

$files = array_merge(glob("img/*.png"), glob("img/*.jpg"));
$files = array_combine($files, array_map("filemtime", $files));
arsort($files);

$latest_file = key($files);