File Uploading Class

CodeIgniter’s File Uploading Class permits files to be uploaded. You can set various preferences, restricting the type and size of the files.

The Process

Uploading a file involves the following general process:

  • An upload form is displayed, allowing a user to select a file and upload it.
  • When the form is submitted, the file is uploaded to the destination you specify.
  • Along the way, the file is validated to make sure it is allowed to be uploaded based on the preferences you set.
  • Once uploaded, the user will be shown a success message.

To demonstrate this process here is brief tutorial. Afterward you’ll find reference information.

Creating the Upload Form

Using a text editor, create a form called upload_form.php. In it, place this code and save it to your application/views/ directory:

<html>
<head>
<title>Upload Form</title>
</head>
<body>

<?php echo $error;?>

<?php echo form_open_multipart('upload/do_upload');?>

<input type="file" name="userfile" size="20" />

<br /><br />

<input type="submit" value="upload" />

</form>

</body>
</html>

You’ll notice we are using a form helper to create the opening form tag. File uploads require a multipart form, so the helper creates the proper syntax for you. You’ll also notice we have an $error variable. This is so we can show error messages in the event the user does something wrong.

The Success Page

Using a text editor, create a form called upload_success.php. In it, place this code and save it to your application/views/ directory:

<html>
<head>
<title>Upload Form</title>
</head>
<body>

<h3>Your file was successfully uploaded!</h3>

<ul>
<?php foreach ($upload_data as $item => $value):?>
<li><?php echo $item;?>: <?php echo $value;?></li>
<?php endforeach; ?>
</ul>

<p><?php echo anchor('upload', 'Upload Another File!'); ?></p>

</body>
</html>

The Controller

Using a text editor, create a controller called Upload.php. In it, place this code and save it to your application/controllers/ directory:

<?php

class Upload extends CI_Controller {

        public function __construct()
        {
                parent::__construct();
                $this->load->helper(array('form', 'url'));
        }

        public function index()
        {
                $this->load->view('upload_form', array('error' => ' ' ));
        }

        public 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('userfile'))
                {
                        $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);
                }
        }
}
?>

The Upload Directory

You’ll need a destination directory for your uploaded images. Create a directory at the root of your CodeIgniter installation called uploads and set its file permissions to 777.

Try it!

To try your form, visit your site using a URL similar to this one:

example.com/index.php/upload/

You should see an upload form. Try uploading an image file (either a jpg, gif, or png). If the path in your controller is correct it should work.

Reference Guide

Initializing the Upload Class

Like most other classes in CodeIgniter, the Upload class is initialized in your controller using the $this->load->library() method:

$this->load->library('upload');

Once the Upload class is loaded, the object will be available using: $this->upload

Setting Preferences

Similar to other libraries, you’ll control what is allowed to be upload based on your preferences. In the controller you built above you set the following preferences:

$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);

// Alternately you can set preferences by calling the ``initialize()`` method. Useful if you auto-load the class:
$this->upload->initialize($config);

The above preferences should be fairly self-explanatory. Below is a table describing all available preferences.

Preferences

The following preferences are available. The default value indicates what will be used if you do not specify that preference.

Preference Default Value Options Description
upload_path None None The path to the directory where the upload should be placed. The directory must be writable and the path can be absolute or relative.
allowed_types None None The mime types corresponding to the types of files you allow to be uploaded. Usually the file extension can be used as the mime type. Can be either an array or a pipe-separated string.
file_name None Desired file name If set CodeIgniter will rename the uploaded file to this name. The extension provided in the file name must also be an allowed file type. If no extension is provided in the original file_name will be used.
file_ext_tolower FALSE TRUE/FALSE (boolean) If set to TRUE, the file extension will be forced to lower case
overwrite FALSE TRUE/FALSE (boolean) If set to true, if a file with the same name as the one you are uploading exists, it will be overwritten. If set to false, a number will be appended to the filename if another with the same name exists.
max_size 0 None The maximum size (in kilobytes) that the file can be. Set to zero for no limit. Note: Most PHP installations have their own limit, as specified in the php.ini file. Usually 2 MB (or 2048 KB) by default.
max_width 0 None The maximum width (in pixels) that the image can be. Set to zero for no limit.
max_height 0 None The maximum height (in pixels) that the image can be. Set to zero for no limit.
min_width 0 None The minimum width (in pixels) that the image can be. Set to zero for no limit.
min_height 0 None The minimum height (in pixels) that the image can be. Set to zero for no limit.
max_filename 0 None The maximum length that a file name can be. Set to zero for no limit.
max_filename_increment 100 None When overwrite is set to FALSE, use this to set the maximum filename increment for CodeIgniter to append to the filename.
encrypt_name FALSE TRUE/FALSE (boolean) If set to TRUE the file name will be converted to a random encrypted string. This can be useful if you would like the file saved with a name that can not be discerned by the person uploading it.
remove_spaces TRUE TRUE/FALSE (boolean) If set to TRUE, any spaces in the file name will be converted to underscores. This is recommended.
detect_mime TRUE TRUE/FALSE (boolean) If set to TRUE, a server side detection of the file type will be performed to avoid code injection attacks. DO NOT disable this option unless you have no other option as that would cause a security risk.
mod_mime_fix TRUE TRUE/FALSE (boolean) If set to TRUE, multiple filename extensions will be suffixed with an underscore in order to avoid triggering Apache mod_mime. DO NOT turn off this option if your upload directory is public, as this is a security risk.

Setting preferences in a config file

If you prefer not to set preferences using the above method, you can instead put them into a config file. Simply create a new file called the upload.php, add the $config array in that file. Then save the file in: config/upload.php and it will be used automatically. You will NOT need to use the $this->upload->initialize() method if you save your preferences in a config file.

Class Reference

class CI_Upload
initialize([array $config = array()[, $reset = TRUE]])
Parameters:
  • $config (array) – Preferences
  • $reset (bool) – Whether to reset preferences (that are not provided in $config) to their defaults
Returns:

CI_Upload instance (method chaining)
Return type:

CI_Upload
do_upload([$field = 'userfile'])
Parameters:
  • $field (string) – Name of the form field
Returns:

TRUE on success, FALSE on failure
Return type:

bool

Performs the upload based on the preferences you’ve set.

Note

By default the upload routine expects the file to come from a form field called userfile, and the form must be of type “multipart”.

<form method="post" action="some_action" enctype="multipart/form-data" />

If you would like to set your own field name simply pass its value to the do_upload() method:

$field_name = "some_field_name";
$this->upload->do_upload($field_name);
display_errors([$open = '<p>'[, $close = '</p>']])
Parameters:
  • $open (string) – Opening markup
  • $close (string) – Closing markup
Returns:

Formatted error message(s)
Return type:

string

Retrieves any error messages if the do_upload() method returned false. The method does not echo automatically, it returns the data so you can assign it however you need.

Formatting Errors

By default the above method wraps any errors within <p> tags. You can set your own delimiters like this:

$this->upload->display_errors('<p>', '</p>');
data([$index = NULL])
Parameters:
  • $data (string) – Element to return instead of the full array
Returns:

Information about the uploaded file
Return type:

mixed

This is a helper method that returns an array containing all of the data related to the file you uploaded. Here is the array prototype:

Array
(
        [file_name]     => mypic.jpg
        [file_type]     => image/jpeg
        [file_path]     => /path/to/your/upload/
        [full_path]     => /path/to/your/upload/jpg.jpg
        [raw_name]      => mypic
        [orig_name]     => mypic.jpg
        [client_name]   => mypic.jpg
        [file_ext]      => .jpg
        [file_size]     => 22.2
        [is_image]      => 1
        [image_width]   => 800
        [image_height]  => 600
        [image_type]    => jpeg
        [image_size_str] => width="800" height="200"
)

To return one element from the array:

$this->upload->data('file_name');       // Returns: mypic.jpg

Here’s a table explaining the above-displayed array items:

Item Description
file_name Name of the file that was uploaded, including the filename extension
file_type File MIME type identifier
file_path Absolute server path to the file
full_path Absolute server path, including the file name
raw_name File name, without the extension
orig_name Original file name. This is only useful if you use the encrypted name option.
client_name File name as supplied by the client user agent, prior to any file name preparation or incrementing
file_ext Filename extension, period included
file_size File size in kilobytes
is_image Whether the file is an image or not. 1 = image. 0 = not.
image_width Image width
image_height Image height
image_type Image type (usually the file name extension without the period)
image_size_str A string containing the width and height (useful to put into an image tag)