获取文件的MIME类型

Question

I'm trying to get mime type of the profile picture they're in format user_id.jpg or gif or png, I experimented with this code but it's not working.

function detectFileMimeType($filename='')
{
    $filename = escapeshellcmd($filename);
    $command = "file -b --mime-type -m /usr/share/misc/magic {$filename}";

    $mimeType = shell_exec($command);

    return trim($mimeType);
}

 function get_avatar($image, $user_id, $account) 
 {
   $imgurl ="http://mypage/files/pictures/picture-" . ($user_id, $mimeType) . ".jpg";

   if (!is_imgurl_good($imgurl)) {
     $imgurl = "http://mypage/sites/all/themes/simple_custom/user.png";
   }
   return $imgurl;
 }

Answer 1

You should be able to get the MIME type of a file fairly easily with built in functions provided by PHP -

function detectFileMimeType($filename='')
    $finfo = finfo_open(FILEINFO_MIME_TYPE); // return mime type 
    $fileglob = glob($filename);
    echo finfo_file($finfo, $fileglob);
    finfo_close($finfo);
}

http://php.net/manual/en/function.finfo-file.php

http://php.net/manual/en/function.glob.php

Answer 2

As well as finfo which works fine, a slightly easier method is to get PHP getimagesize function return, as this will return the MIME type as extracted from the file:

$file = "blah/blahblah/bubbles.jpg";
$fileTypeData = getimagesize($file);
$fileTypeData['mime'] = The Mime type of the image file.