Finfo_file on uploaded file to determine mime-type

Question

Im trying to determine the mime-type of an uploaded file, i want to use fileinfo(), this is what ive been trying, it isnt working:

$uploadedfile = $_FILES[\'         


        

Answer 1

I know this is a bit old, but since you're using the $_FILES super global, can you use the type key of the file array (i.e. $_FILES['soup']['type']) rather than having the server check once the file is uploaded?

Answer 2

I use the finfo() buffer() function as well as file_get_contents() from the php platform as below

$finfo = new finfo(FILEINFO_MIME);
$mimetype = $finfo->buffer(file_get_contents($filename)); #gives you mime type

you need to be on php 5.3 or higher and make sure you have the finfo() extension installed. for linux extension=fileinfo. and in windows: php_fileinfo.dll

you can have an array of accepted mime types and then check if it exists in that array

$acceptedMime = [];
if(in_array($mimetype, $acceptedMime, true) === true){
  #mime type is valid. Proceed!
}

Another alternative to avoid having to check mime types would be to store file uploads completely out of the document root folder.

Answer 3

You should be passing the path to the finfo_file function not the filename.

<?php 
if (isset($_FILES['soup']['tmp_name'])) {
    $finfo = finfo_open(FILEINFO_MIME_TYPE);
    $mime = finfo_file($finfo, $_FILES['soup']['tmp_name']);
    if ($mime == 'application/msword') {
        //Its a doc format do something
    }
    finfo_close($finfo);
}
?>