public function toMimeType($extension)
    {
        $extension = strtolower($extension);

        if (array_key_exists($extension, $this->dict)) {
            return $this->dict[$extension];
        }
    }
public function toMimeType($extension)
    {
        $extension = strtolower($extension);

        if (array_key_exists($extension, $this->dict)) {
            return $this->dict[$extension];
        }
    }
public function toMimeType ( $ extension ) { $ extension = strtolower ( $ extension ) ; if ( array_key_exists ( $ extension , $ this -> dict ) ) { return $ this -> dict [ $ extension ] ; } }
Convert a file extension to the proper mime type.

@param string $extension
@return string|null
Convert a file extension to the proper mime type .