Undefined index: extension for folders in PHP - php

Question

I wanted to have a script which would turn all my images into thumbnails and save these new thumbnails in a new folder.
I had luck an found a code which worked almost perfectly from
http://webcheatsheet.com/php/create_thumbnail_images.php
The only problem is that if there is a folder in the "uploads"-folder (defined at the end of the code) then I get the "Notice: Undefined index: extension".
The code doesn't get stuck and I still get my thumbnails, but the error message is annoying.
I tried to put in an isset-function, but did something wrong as I still didn't manage to stop the script from acting upon the folders. The code doesn't react similarly on any other files, so it seems to be the lack of an extension in the folder-name that bothers the code.
I was able to make it easy and simply remove any folders from the "uploads"-folder and put the thumbnails' path somewhere else, but I'd also like to get it to work without error-messages in case I happen to have folders in these image folders.
// parse path for the extension
$info = pathinfo($pathToImages . $fname);
// continue only if this is a JPEG image
//print_r($info);
if ( strtolower($info['extension']) == 'jpg' ) { // reacts on the folder with no extension name and gives an error
echo "Creating thumbnail for {$fname} <br />";
// load image and get image size
$img = imagecreatefromjpeg( "{$pathToImages}{$fname}" );
$width = imagesx( $img );
$height = imagesy( $img );
// calculate thumbnail size
$new_width = $thumbWidth;
$new_height = floor( $height * ( $thumbWidth / $width ) );
// create a new temporary image
$tmp_img = imagecreatetruecolor( $new_width, $new_height );
// copy and resize old image into new image
imagecopyresized( $tmp_img, $img, 0, 0, 0, 0, $new_width, $new_height, $width, $height );
// save thumbnail into a file
imagejpeg( $tmp_img, "{$pathToThumbs}{$fname}" );
}
}
The full code in the link above.

Answer 1

The pathinfo docs explain:
Note:
If the path does not have an extension, no extension element will be
returned
So to avoid the notice you just need to check that value is available before trying to use it:
if( isset($info['extension']) AND strtolower($info['extension']) == 'jpg'){
//do sutff
}
Or instead of isset(...) you could use array_keys_exists('extension', $info).