PHP Random Filename - PHP function to generate random filename with same extension as given filename, e.g. to avoid filename collisions when uploading

random-filename.php

<?php

/*-------------------------------------------------------------
 * Generate a random 32 character filename with same extension
 * (including no extension) as the filename provided
 *-------------------------------------------------------------*/
function randomFilename( $originalFilename ) {
    
    $filenameParts = explode( '.', $originalFilename );          // Break apart the filename
    $fileExtension = $filenameParts[sizeof($filenameParts) - 1]; // To get the file extension

    $randFilename = md5( $originalFilename.rand( 1, 100000 ) );  // Generate a random 32 char filename
    $randFilename = $randFilename.'.'.$fileExtension;            // Add on file extension
    $randFilename = strtolower( $randFilename );                 // Force to lowercase
    
    return $randFilename;
}

?>