Codeigniter, testing if file uploader has file - php

Question

I have the following code in my view:
if (isset($stockists)) {
$id = $stockists->ID;
echo form_open_multipart($system_settings['admin_folder'].'/stockists/form/'.$id);
}
else {
echo form_open_multipart($system_settings['admin_folder'].'/stockists/form/');
}
<?php echo "<input type='file' name='userfile' size='20' />"; ?>
There's lots of other text input fields in there that are sent to a database on submit. The file up loader is what I'm interested in though.
In my controller function, how can I check if a file exists in the up-loader after submit?
The following retruns false:
$image = ($_FILES['userfile']);
I need to check in a conditional statement if a file exists in the uploader. So for example:
if ($_FILES['userfile']) {
//do
}
But this method does not work.

Answer 1

The super global $_FILES
$_FILES['userfile'] isn't a boolean.
if (strlen($_FILES['userfile']['tmp_name']) > 0) {
// Yes, is uploaded
}
In the array, you've also error:
echo $_FILES['userfile']['error'];
CodeIgniter Approach
CodeIgniter has an upload class that can do the work for you.
CodeIgniter's File Uploading Class permits files to be uploaded. You can set various preferences, restricting the type and size of the files.
Below an example from the CodeIgniter documentation:
<?php
class Upload extends CI_Controller {
function __construct()
{
parent::__construct();
$this->load->helper(array('form', 'url'));
}
function index()
{
$this->load->view('upload_form', array('error' => ' ' ));
}
function do_upload()
{
$config['upload_path'] = './uploads/';
$config['allowed_types'] = 'gif|jpg|png';
$config['max_size'] = '100';
$config['max_width'] = '1024';
$config['max_height'] = '768';
$this->load->library('upload', $config);
if ( ! $this->upload->do_upload())
{
$error = array('error' => $this->upload->display_errors());
$this->load->view('upload_form', $error);
}
else
{
$data = array('upload_data' => $this->upload->data());
$this->load->view('upload_success', $data);
}
}
}
?>
See for full examples the documentation: CI File Upload Class