- -

Helper Functions

- -

Helpers, as the name suggests, help you with tasks. Each helper file is simply a collection of functions in a particular -category. There are URL Helpers, that assist in creating links, there are Form Helpers -that help you create form elements, Text Helpers perform various text formatting routines, -Cookie Helpers set and read cookies, File Helpers help you deal with files, etc. -

- -

Unlike most other systems in CodeIgniter, Helpers are not written in an Object Oriented format. They are simple, procedural functions. -Each helper function performs one specific task, with no dependence on other functions.

- -

Helpers are intentionally kept very simple so that they can be used within your View Files with a minimal amount of code. -This is important if you intend to have designers or non-programmer will be working with your view files, since it keeps the code to a minimum. -

- -

CodeIgniter does not load Helper Files by default, so the first step in using -a Helper is to load it. Once loaded, it becomes globally available in your controller and views.

- -

Loading a Helper

- -

Loading a helper file is quite simple using the following function:

- -$this->load->helper('name'); - -

Where name is the file name of the helper, without the .php file extension or the "helper" part.

- -

For example, to load the URL Helper file, which is named url_helper.php, you would do this:

- -$this->load->helper('url'); - -

A helper can be loaded anywhere within your controller functions (or even within your View files, although that's not a good practice), -as long as you load it before you use it. You can load your helpers in your controller constructor so that they become available -automatically in any function, or you can load a helper in a specific function that needs it.

- -

Note: The Helper loading function above does not return a value, so don't try to assign it to a variable. Just use it as shown.

- -

Auto-loading Helpers

- -

If you find that you need a particular helper globally throughout your application, you can tell CodeIgniter to auto-load it during system initialization. -This is done by opening the application/config/autoload.php file and adding the helper to the autoload array.

- - -

Using a Helper

- -

Once you've loaded the Helper File containing the function you intend to use, you'll call it the way you would a standard PHP function.

- -

For example, to create a link using the anchor() function in one of your view files you would do this:

- -<?=anchor('blog/comments', 'Click Here');?> - -

Where "Click Here" is the name of the link, and "blog/comments" is the URI to the controller/function you wish to link to.

- - -

Now What?

- -

In the Table of Contents you'll find a list of all the available Helper Files. Browse each one to see what they do.

- - -

You'll notice that in addition to the smiley helper we are using the Table Class.

In your application/views/ folder, create a file called smiley_view.php and place this code in it:

get_clickable_smileys()

Returns an array containing your smiley images wrapped in a cliackable link. You must supply the URL to your smiley folder +

Returns an array containing your smiley images wrapped in a clickable link. You must supply the URL to your smiley folder via the first parameter:

parse_smileys()

Takes a string of text as input and replaces any contained plain text smileys into the image -equivalent. The first parameter must contain your string, the second must contain the the URL to your smiley folder:

CodeIgniter User Guide Version 1.6.1

Helper Functions

Loading a Helper

Auto-loading Helpers

Using a Helper

Now What?

get_clickable_smileys()

parse_smileys()