Question

How to create a file (name_of_file . file_extension), by mime type? The list of mimes is dynamic.

Example:

MIME                   Extension
application/msword  |  .doc
text/plain          |  .txt
text/css            |  .css

I dont wanna use array(“mime” => “extension”);

I have the mime type, but i need the file extension.

Answer 1

To avoid using a lookup table (at least avoid you having to define one) you can use finfo_file.

echo finfo_file('myfile.jpg', finfo_open(FILEINFO_MIME_TYPE)); // output: image/jpg

If you’re on 5.0, you may try mime_content_type (But keep in mind this is deprecated, so if you’re looking for upgrade-compatible, you may want to default to the new finfo_file when possible):

echo mime_content_type('myfile.jpg'); // output: image/jpg

---

// When possible, it will use upgraded finfo_file, but will default back
// to content_mime_type when necessary
function getMimeType($file){
  if (function_exists('finfo_file') && defined('FILEINFO_MIME_TYPE')){
    $return_mime = finfo_open(FILEINFO_MIME_TYPE);
    return finfo_file($file, $return_mime);
  }
  return content_mime_type($file);
}