function FileSystem::createFilename
Creates a full file path from a directory and filename.
If a file with the specified name already exists, an alternative will be used.
Parameters
string $basename: The filename.
string $directory: The directory or parent URI.
Return value
string File path consisting of $directory and a unique filename based off of $basename.
Overrides FileSystemInterface::createFilename
1 call to FileSystem::createFilename()
- FileSystem::getDestinationFilename in core/lib/ Drupal/ Core/ File/ FileSystem.php 
- Determines the destination path for a file.
File
- 
              core/lib/ Drupal/ Core/ File/ FileSystem.php, line 581 
Class
- FileSystem
- Provides helpers to operate on files and stream wrappers.
Namespace
Drupal\Core\FileCode
public function createFilename($basename, $directory) {
  $original = $basename;
  // Strip control characters (ASCII value < 32). Though these are allowed in
  // some filesystems, not many applications handle them well.
  $basename = preg_replace('/[\\x00-\\x1F]/u', '_', $basename);
  if (preg_last_error() !== PREG_NO_ERROR) {
    throw new FileException(sprintf("Invalid filename '%s'", $original));
  }
  if (substr(PHP_OS, 0, 3) == 'WIN') {
    // These characters are not allowed in Windows filenames.
    $basename = str_replace([
      ':',
      '*',
      '?',
      '"',
      '<',
      '>',
      '|',
    ], '_', $basename);
  }
  // A URI or path may already have a trailing slash or look like "public://".
  if (substr($directory, -1) == '/') {
    $separator = '';
  }
  else {
    $separator = '/';
  }
  $destination = $directory . $separator . $basename;
  if (file_exists($destination)) {
    // Destination file already exists, generate an alternative.
    $pos = strrpos($basename, '.');
    if ($pos !== FALSE) {
      $name = substr($basename, 0, $pos);
      $ext = substr($basename, $pos);
    }
    else {
      $name = $basename;
      $ext = '';
    }
    $counter = 0;
    do {
      $destination = $directory . $separator . $name . '_' . $counter++ . $ext;
    } while (file_exists($destination));
  }
  return $destination;
}Buggy or inaccurate documentation? Please file an issue. Need support? Need help programming? Connect with the Drupal community.
