File uploads

Uploading files is a common functionality to many PHP applications. So common that PHP provides a convenient global $_FILES variable we can use to access uploaded files, or errors behind the file upload tries.

Let's take a look at the following simple file upload form:

<form method="post" enctype="multipart/form-data">
  <input type="file" name="photo" />
  <input type="file" name="article" />
  <input type="submit" name="submit" value="Upload" />
</form>

In order for PHP to pick up the files, we need to set the form method value to post, and enctype to multipart/form-data. Once submitted, PHP will pick it up and fill in the $_FILES variable appropriately:

array(2) { 
  ["photo"] => array(5) { 
    ["name"] => string(9) "photo.jpg" 
    ["type"] => string(10) "image/jpeg" 
    ["tmp_name"] => string(14) "/tmp/phpGutI91" 
    ["error"] => int(0) 
    ["size"] => int(42497) 
  } 
  ["article"] => array(5) { 
    ["name"] => string...