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.
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 applications/views/ folder:
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 applications/views/ folder:
Using a text editor, create a controller called upload.php. In it, place this code and save it to your applications/controllers/ folder:
The Upload Folder
You'll need a destination folder for your uploaded images. Create a folder at the root of your CodeIgniter installation called uploads and set its file permissions to 777.
To try your form, visit your site using a URL similar to this one:
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.
Initializing the Upload Class
Like most other classes in CodeIgniter, the Upload class is initialized in your controller using the $this->load->library function:
Once the Upload class is loaded, the object will be available using: $this->upload
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';
// Alternately you can set preferences by calling the initialize function. Useful if you auto-load the class:
The above preferences should be fairly self-explanatory. Below is a table describing all available preferences.
The following preferences are available. The default value indicates what will be used if you do not specify that preference.
|upload_path||None||None||The path to the folder where the upload should be placed. The folder 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. Separate multiple types with a pipe.|
|file_name||None||Desired file name||
If set CodeIgniter will rename the uploaded file to this name.
Note:The filename should not include a file extension.
|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 file can be. Set to zero for no limit.|
|max_height||0||None||The maximum height (in pixels) that the file 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.|
|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.|
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 function if you save your preferences in a config file.
The following functions are available
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 a "multipart type:
<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 function:
$field_name = "some_field_name";
Retrieves any error messages if the do_upload() function returned false. The function does not echo automatically, it returns the data so you can assign it however you need.
By default the above function wraps any errors within <p> tags. You can set your own delimiters like this:
This is a helper function that returns an array containing all of the data related to the file you uploaded. Here is the array prototype:
[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
[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"
Here is an explanation of the above array items.
|file_name||The name of the file that was uploaded including the file extension.|
|file_type||The file's Mime type|
|file_path||The absolute server path to the file|
|full_path||The absolute server path including the file name|
|raw_name||The file name without the extension|
|orig_name||The original file name. This is only useful if you use the encrypted name option.|
|file_ext||The file extension with period|
|file_size||The file size in kilobytes|
|is_image||Whether the file is an image or not. 1 = image. 0 = not.|
|image_type||Image type. Typically the file extension without the period.|
|image_size_str||A string containing the width and height. Useful to put into an image tag.|