Change Filenames to Upper or Lower Case (in bulk) in PHP

Atlast I overcame my laziness and wrote a long overdue script to change filenames. Before writing this code, I couldn’t find a reasonable solution in PHP despite a major search operation. The need, infact, arose when I copied my PHP code from windows to linux machine, and it refused to show alot of images, which never gave any problem in windows as windows isn’t case sensitive. Here’s the script to change filenames from lower case to upper case and vice versa.

//$DIRNAME = "/srv/www/htdocs/kbs/pollimages" ; // for linux
$DIRNAME = "C:\\gohar\\gohar data\\ngc\\ngckbs\\pollimages" ;
$TO = "LOW" ; // UP or LOW
$SPECIAL_CHAR_REPLACE = "_" ; // To replace the special characters with
$REMOVE_SPECIAL_CHAR = true ; // will replace special characters with the value given in $SPECIAL_CHAR_REPLACE, if set to true
$REMOVE_REDUNDENCY = true ; // will remove repetitive $SPECIAL_CHAR_REPLACE, if set to true
$CONCAT = "__x_x__" ; // for temporarily replace 

$dir = dir($DIRNAME);
while (false !== ($old_filename = $dir->read())) {
	if(filetype($DIRNAME."/".$old_filename) == "file"){
		// change case
		$new_filename = ($TO == "UP" ? strtoupper($old_filename) : strtolower($old_filename)) ;
		// replace special characters
		if($SPECIAL_CHAR_REPLACE){
			$new_filename = ereg_replace("[^a-z0-9.]" , $SPECIAL_CHAR_REPLACE , $new_filename);
		}
		// remove repetition after replacement
		if($REMOVE_REDUNDENCY){
			$new_filename = ereg_replace("[$SPECIAL_CHAR_REPLACE]{1,}" , $SPECIAL_CHAR_REPLACE , $new_filename);
		}
		// remove replacement from end
		if(substr($str , -1) == $SPECIAL_CHAR_REPLACE){
			$new_filename = substr($new_filename , 0 , -1);
		}
		// first rename
		@rename($DIRNAME."/".$old_filename, $DIRNAME."/".$CONCAT.$new_filename) ;
		// second rename
		@rename($DIRNAME."/".$CONCAT.$new_filename, $DIRNAME."/".$new_filename) ;
		echo $DIRNAME."/".$new_filename."<br>" ;
	}
}
$dir-&gt;close();

$CONCAT is required because in windows, atleast in my case, it doesn’t change the case of file if the filename is to be kept the same, as it doesn’t consider it a different filename. So I had to rename it using $CONCAT and then remove this concatenation. This gave me a filename with changed case, thus changing the filename to lower case or upper case. This script also removes special characters and replaces those with any mentioned replacement in $SPECIAL_CHAR_REPLACE and then removes redundency of replacement character.

Hope it serves someone’s purpose.