user_guide_src/source/libraries/form_validation.rst


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###############
Form Validation
###############

CodeIgniter provides a comprehensive form validation and data prepping
class that helps minimize the amount of code you'll write.

-  `Overview <#overview>`_
-  `Form Validation Tutorial <#tutorial>`_

   -  `The Form <#theform>`_
   -  `The Success Page <#thesuccesspage>`_
   -  `The Controller <#thecontroller>`_
   -  `Setting Validation Rules <#validationrules>`_
   -  `Setting Validation Rules Using an
      Array <#validationrulesasarray>`_
   -  `Cascading Rules <#cascadingrules>`_
   -  `Prepping Data <#preppingdata>`_
   -  `Re-populating the Form <#repopulatingform>`_
   -  `Callbacks <#callbacks>`_
   -  `Setting Error Messages <#settingerrors>`_
   -  `Changing the Error Delimiters <#errordelimiters>`_
   -  `Translating Field Names <#translatingfn>`_
   -  `Showing Errors Individually <#individualerrors>`_
   -  `Saving Sets of Validation Rules to a Config
      File <#savingtoconfig>`_
   -  `Using Arrays as Field Names <#arraysasfields>`_

-  `Rule Reference <#rulereference>`_
-  `Prepping Reference <#preppingreference>`_
-  `Function Reference <#functionreference>`_
-  `Helper Reference <#helperreference>`_

********
Overview
********

Before explaining CodeIgniter's approach to data validation, let's
describe the ideal scenario:

#. A form is displayed.
#. You fill it in and submit it.
#. If you submitted something invalid, or perhaps missed a required
   item, the form is redisplayed containing your data along with an
   error message describing the problem.
#. This process continues until you have submitted a valid form.

On the receiving end, the script must:

#. Check for required data.
#. Verify that the data is of the correct type, and meets the correct
   criteria. For example, if a username is submitted it must be
   validated to contain only permitted characters. It must be of a
   minimum length, and not exceed a maximum length. The username can't
   be someone else's existing username, or perhaps even a reserved word.
   Etc.
#. Sanitize the data for security.
#. Pre-format the data if needed (Does the data need to be trimmed? HTML
   encoded? Etc.)
#. Prep the data for insertion in the database.

Although there is nothing terribly complex about the above process, it
usually requires a significant amount of code, and to display error
messages, various control structures are usually placed within the form
HTML. Form validation, while simple to create, is generally very messy
and tedious to implement.

************************
Form Validation Tutorial
************************

What follows is a "hands on" tutorial for implementing CodeIgniters Form
Validation.

In order to implement form validation you'll need three things:

#. A :doc:`View <../general/views>` file containing a form.
#. A View file containing a "success" message to be displayed upon
   successful submission.
#. A :doc:`controller <../general/controllers>` function to receive and
   process the submitted data.

Let's create those three things, using a member sign-up form as the
example.

The Form
========

Using a text editor, create a form called myform.php. In it, place this
code and save it to your applications/views/ folder:

<html> <head> <title>My Form</title> </head> <body> <?php echo
validation_errors(); ?> <?php echo form_open('form'); ?>
<h5>Username</h5> <input type="text" name="username" value="" size="50"
/> <h5>Password</h5> <input type="text" name="password" value=""
size="50" /> <h5>Password Confirm</h5> <input type="text"
name="passconf" value="" size="50" /> <h5>Email Address</h5> <input
type="text" name="email" value="" size="50" /> <div><input type="submit"
value="Submit" /></div> </form> </body> </html>

The Success Page
================

Using a text editor, create a form called formsuccess.php. In it, place
this code and save it to your applications/views/ folder:

<html> <head> <title>My Form</title> </head> <body> <h3>Your form was
successfully submitted!</h3> <p><?php echo anchor('form', 'Try it
again!'); ?></p> </body> </html>

The Controller
==============

Using a text editor, create a controller called form.php. In it, place
this code and save it to your applications/controllers/ folder:

<?php class Form extends CI_Controller { function index() {
$this->load->helper(array('form', 'url'));
$this->load->library('form_validation'); if
($this->form_validation->run() == FALSE) { $this->load->view('myform');
} else { $this->load->view('formsuccess'); } } } ?>

Try it!
=======

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

	example.com/index.php/form/

If you submit the form you should simply see the form reload. That's
because you haven't set up any validation rules yet.

**Since you haven't told the Form Validation class to validate anything
yet, it returns FALSE (boolean false) by default. The run() function
only returns TRUE if it has successfully applied your rules without any
of them failing.**

Explanation
===========

You'll notice several things about the above pages:

The form (myform.php) is a standard web form with a couple exceptions:

#. It uses a form helper to create the form opening. Technically, this
   isn't necessary. You could create the form using standard HTML.
   However, the benefit of using the helper is that it generates the
   action URL for you, based on the URL in your config file. This makes
   your application more portable in the event your URLs change.
#. At the top of the form you'll notice the following function call:
   ::

	<?php echo validation_errors(); ?>

   This function will return any error messages sent back by the
   validator. If there are no messages it returns an empty string.

The controller (form.php) has one function: index(). This function
initializes the validation class and loads the form helper and URL
helper used by your view files. It also runs the validation routine.
Based on whether the validation was successful it either presents the
form or the success page.

Setting Validation Rules
========================

CodeIgniter lets you set as many validation rules as you need for a
given field, cascading them in order, and it even lets you prep and
pre-process the field data at the same time. To set validation rules you
will use the set_rules() function::

	$this->form_validation->set_rules();

The above function takes **three** parameters as input:

#. The field name - the exact name you've given the form field.
#. A "human" name for this field, which will be inserted into the error
   message. For example, if your field is named "user" you might give it
   a human name of "Username".
#. The validation rules for this form field.

.. note:: If you would like the field
	name to be stored in a language file, please see `Translating Field
	Names <#translatingfn>`_.

Here is an example. In your controller (form.php), add this code just
below the validation initialization function::

	 $this->form_validation->set_rules('username', 'Username', 'required'); $this->form_validation->set_rules('password', 'Password', 'required'); $this->form_validation->set_rules('passconf', 'Password Confirmation', 'required'); $this->form_validation->set_rules('email', 'Email', 'required');

Your controller should now look like this:

<?php class Form extends CI_Controller { function index() {
$this->load->helper(array('form', 'url'));
$this->load->library('form_validation');
$this->form_validation->set_rules('username', 'Username', 'required');
$this->form_validation->set_rules('password', 'Password', 'required');
$this->form_validation->set_rules('passconf', 'Password Confirmation',
'required'); $this->form_validation->set_rules('email', 'Email',
'required'); if ($this->form_validation->run() == FALSE) {
$this->load->view('myform'); } else { $this->load->view('formsuccess');
} } } ?>

Now submit the form with the fields blank and you should see the error
messages. If you submit the form with all the fields populated you'll
see your success page.

.. note:: The form fields are not yet being re-populated with the data
	when there is an error. We'll get to that shortly.

Setting Rules Using an Array
============================

Before moving on it should be noted that the rule setting function can
be passed an array if you prefer to set all your rules in one action. If
you use this approach you must name your array keys as indicated::

	 $config = array(                array(                      'field'   => 'username',                       'label'   => 'Username',                       'rules'   => 'required'                   ),                array(                      'field'   => 'password',                       'label'   => 'Password',                       'rules'   => 'required'                   ),                array(                      'field'   => 'passconf',                       'label'   => 'Password Confirmation',                       'rules'   => 'required'                   ),                   array(                      'field'   => 'email',                       'label'   => 'Email',                       'rules'   => 'required'                   )             );  $this->form_validation->set_rules($config);

Cascading Rules
===============

CodeIgniter lets you pipe multiple rules together. Let's try it. Change
your rules in the third parameter of rule setting function, like this::

	 $this->form_validation->set_rules('username', 'Username', 'required|min_length[5]|max_length[12]|is_unique[users.username]'); $this->form_validation->set_rules('password', 'Password', 'required|matches[passconf]'); $this->form_validation->set_rules('passconf', 'Password Confirmation', 'required'); $this->form_validation->set_rules('email', 'Email', 'required|valid_email|is_unique[users.email]');

The above code sets the following rules:

#. The username field be no shorter than 5 characters and no longer than
   12.
#. The password field must match the password confirmation field.
#. The email field must contain a valid email address.

Give it a try! Submit your form without the proper data and you'll see
new error messages that correspond to your new rules. There are numerous
rules available which you can read about in the validation reference.

Prepping Data
=============

In addition to the validation functions like the ones we used above, you
can also prep your data in various ways. For example, you can set up
rules like this::

	 $this->form_validation->set_rules('username', 'Username', 'trim|required|min_length[5]|max_length[12]|xss_clean'); $this->form_validation->set_rules('password', 'Password', 'trim|required|matches[passconf]|md5'); $this->form_validation->set_rules('passconf', 'Password Confirmation', 'trim|required'); $this->form_validation->set_rules('email', 'Email', 'trim|required|valid_email');

In the above example, we are "trimming" the fields, converting the
password to MD5, and running the username through the "xss_clean"
function, which removes malicious data.

**Any native PHP function that accepts one parameter can be used as a
rule, like htmlspecialchars, trim, MD5, etc.**

.. note:: You will generally want to use the prepping functions
	**after** the validation rules so if there is an error, the original
	data will be shown in the form.

Re-populating the form
======================

Thus far we have only been dealing with errors. It's time to repopulate
the form field with the submitted data. CodeIgniter offers several
helper functions that permit you to do this. The one you will use most
commonly is::

	set_value('field name')

Open your myform.php view file and update the **value** in each field
using the set_value() function:

**Don't forget to include each field name in the set_value()
functions!**

<html> <head> <title>My Form</title> </head> <body> <?php echo
validation_errors(); ?> <?php echo form_open('form'); ?>
<h5>Username</h5> <input type="text" name="username" value="<?php echo
set_value('username'); ?>" size="50" /> <h5>Password</h5> <input
type="text" name="password" value="<?php echo set_value('password');
?>" size="50" /> <h5>Password Confirm</h5> <input type="text"
name="passconf" value="<?php echo set_value('passconf'); ?>" size="50"
/> <h5>Email Address</h5> <input type="text" name="email" value="<?php
echo set_value('email'); ?>" size="50" /> <div><input type="submit"
value="Submit" /></div> </form> </body> </html>
Now reload your page and submit the form so that it triggers an error.
Your form fields should now be re-populated

.. note:: The `Function Reference <#functionreference>`_ section below
	contains functions that permit you to re-populate <select> menus, radio
	buttons, and checkboxes.

**Important Note:** If you use an array as the name of a form field, you
must supply it as an array to the function. Example::

	<input type="text" name="colors[]" value="<?php echo set_value('colors[]'); ?>" size="50" />

For more info please see the `Using Arrays as Field
Names <#arraysasfields>`_ section below.

Callbacks: Your own Validation Functions
========================================

The validation system supports callbacks to your own validation
functions. This permits you to extend the validation class to meet your
needs. For example, if you need to run a database query to see if the
user is choosing a unique username, you can create a callback function
that does that. Let's create a example of this.

In your controller, change the "username" rule to this::

	$this->form_validation->set_rules('username', 'Username', 'callback_username_check');

Then add a new function called username_check to your controller.
Here's how your controller should now look:

<?php class Form extends CI_Controller { public function index() {
$this->load->helper(array('form', 'url'));
$this->load->library('form_validation');
$this->form_validation->set_rules('username', 'Username',
'callback_username_check');
$this->form_validation->set_rules('password', 'Password', 'required');
$this->form_validation->set_rules('passconf', 'Password Confirmation',
'required'); $this->form_validation->set_rules('email', 'Email',
'required\|is_unique[users.email]'); if ($this->form_validation->run()
== FALSE) { $this->load->view('myform'); } else {
$this->load->view('formsuccess'); } } public function
username_check($str) { if ($str == 'test') {
$this->form_validation->set_message('username_check', 'The %s field
can not be the word "test"'); return FALSE; } else { return TRUE; } } }
?>
Reload your form and submit it with the word "test" as the username. You
can see that the form field data was passed to your callback function
for you to process.

To invoke a callback just put the function name in a rule, with
"callback\_" as the rule **prefix**. If you need to receive an extra
parameter in your callback function, just add it normally after the
function name between square brackets, as in: "callback_foo**[bar]**",
then it will be passed as the second argument of your callback function.

.. note:: You can also process the form data that is passed to your
	callback and return it. If your callback returns anything other than a
	boolean TRUE/FALSE it is assumed that the data is your newly processed
	form data.

Setting Error Messages
======================

All of the native error messages are located in the following language
file: language/english/form_validation_lang.php

To set your own custom message you can either edit that file, or use the
following function::

	$this->form_validation->set_message('rule', 'Error Message');

Where rule corresponds to the name of a particular rule, and Error
Message is the text you would like displayed.

If you include %s in your error string, it will be replaced with the
"human" name you used for your field when you set your rules.

In the "callback" example above, the error message was set by passing
the name of the function::

	$this->form_validation->set_message('username_check')

You can also override any error message found in the language file. For
example, to change the message for the "required" rule you will do this::

	$this->form_validation->set_message('required', 'Your custom message here');

Translating Field Names
=======================

If you would like to store the "human" name you passed to the
set_rules() function in a language file, and therefore make the name
able to be translated, here's how:

First, prefix your "human" name with lang:, as in this example::

	 $this->form_validation->set_rules('first_name', 'lang:first_name', 'required');

Then, store the name in one of your language file arrays (without the
prefix)::

	$lang['first_name'] = 'First Name';

.. note:: If you store your array item in a language file that is not
	loaded automatically by CI, you'll need to remember to load it in your
	controller using::

	$this->lang->load('file_name');

See the :doc:`Language Class <language>` page for more info regarding
language files.

Changing the Error Delimiters
=============================

By default, the Form Validation class adds a paragraph tag (<p>) around
each error message shown. You can either change these delimiters
globally or individually.

#. **Changing delimiters Globally**
   To globally change the error delimiters, in your controller function,
   just after loading the Form Validation class, add this:

   ::

	$this->form_validation->set_error_delimiters('<div class="error">', '</div>');

   In this example, we've switched to using div tags.

#. **Changing delimiters Individually**
   Each of the two error generating functions shown in this tutorial can
   be supplied their own delimiters as follows:

   ::

	<?php echo form_error('field name', '<div class="error">', '</div>'); ?>

   Or:

   ::

	<?php echo validation_errors('<div class="error">', '</div>'); ?>


Showing Errors Individually
===========================

If you prefer to show an error message next to each form field, rather
than as a list, you can use the form_error() function.

Try it! Change your form so that it looks like this:

<h5>Username</h5> <?php echo form_error('username'); ?> <input
type="text" name="username" value="<?php echo set_value('username');
?>" size="50" /> <h5>Password</h5> <?php echo form_error('password');
?> <input type="text" name="password" value="<?php echo
set_value('password'); ?>" size="50" /> <h5>Password Confirm</h5> <?php
echo form_error('passconf'); ?> <input type="text" name="passconf"
value="<?php echo set_value('passconf'); ?>" size="50" /> <h5>Email
Address</h5> <?php echo form_error('email'); ?> <input type="text"
name="email" value="<?php echo set_value('email'); ?>" size="50" />
If there are no errors, nothing will be shown. If there is an error, the
message will appear.

**Important Note:** If you use an array as the name of a form field, you
must supply it as an array to the function. Example::

	<?php echo form_error('options[size]'); ?> <input type="text" name="options[size]" value="<?php echo set_value("options[size]"); ?>" size="50" />

For more info please see the `Using Arrays as Field
Names <#arraysasfields>`_ section below.

************************************************
Saving Sets of Validation Rules to a Config File
************************************************

A nice feature of the Form Validation class is that it permits you to
store all your validation rules for your entire application in a config
file. You can organize these rules into "groups". These groups can
either be loaded automatically when a matching controller/function is
called, or you can manually call each set as needed.

How to save your rules
======================

To store your validation rules, simply create a file named
form_validation.php in your application/config/ folder. In that file
you will place an array named $config with your rules. As shown earlier,
the validation array will have this prototype::

	 $config = array(                array(                      'field'   => 'username',                       'label'   => 'Username',                       'rules'   => 'required'                   ),                array(                      'field'   => 'password',                       'label'   => 'Password',                       'rules'   => 'required'                   ),                array(                      'field'   => 'passconf',                       'label'   => 'Password Confirmation',                       'rules'   => 'required'                   ),                   array(                      'field'   => 'email',                       'label'   => 'Email',                       'rules'   => 'required'                   )             );

Your validation rule file will be loaded automatically and used when you
call the run() function.

Please note that you MUST name your array $config.

Creating Sets of Rules
======================

In order to organize your rules into "sets" requires that you place them
into "sub arrays". Consider the following example, showing two sets of
rules. We've arbitrarily called these two rules "signup" and "email".
You can name your rules anything you want::

	$config = array(                  'signup' => array(                                     array(                                             'field' => 'username',                                             'label' => 'Username',                                             'rules' => 'required'                                          ),                                     array(                                             'field' => 'password',                                             'label' => 'Password',                                             'rules' => 'required'                                          ),                                     array(                                             'field' => 'passconf',                                             'label' => 'PasswordConfirmation',                                             'rules' => 'required'                                          ),                                     array(                                             'field' => 'email',                                             'label' => 'Email',                                             'rules' => 'required'                                          )                                     ),                  'email' => array(                                     array(                                             'field' => 'emailaddress',                                             'label' => 'EmailAddress',                                             'rules' => 'required|valid_email'                                          ),                                     array(                                             'field' => 'name',                                             'label' => 'Name',                                             'rules' => 'required|alpha'                                          ),                                     array(                                             'field' => 'title',                                             'label' => 'Title',                                             'rules' => 'required'                                          ),                                     array(                                             'field' => 'message',                                             'label' => 'MessageBody',                                             'rules' => 'required'                                          )                                     )                                          );

Calling a Specific Rule Group
=============================

In order to call a specific group you will pass its name to the run()
function. For example, to call the signup rule you will do this::

	 if ($this->form_validation->run('signup') == FALSE) {    $this->load->view('myform'); } else {    $this->load->view('formsuccess'); }

Associating a Controller Function with a Rule Group
===================================================

An alternate (and more automatic) method of calling a rule group is to
name it according to the controller class/function you intend to use it
with. For example, let's say you have a controller named Member and a
function named signup. Here's what your class might look like::

	 <?php class Member extends CI_Controller {     function signup()    {             $this->load->library('form_validation');                    if ($this->form_validation->run() == FALSE)       {          $this->load->view('myform');       }       else       {          $this->load->view('formsuccess');       }    } } ?>

In your validation config file, you will name your rule group
member/signup::

	$config = array(            'member/signup' => array(                                     array(                                             'field' => 'username',                                             'label' => 'Username',                                             'rules' => 'required'                                          ),                                     array(                                             'field' => 'password',                                             'label' => 'Password',                                             'rules' => 'required'                                          ),                                     array(                                             'field' => 'passconf',                                             'label' => 'PasswordConfirmation',                                             'rules' => 'required'                                          ),                                     array(                                             'field' => 'email',                                             'label' => 'Email',                                             'rules' => 'required'                                          )                                     )                );

When a rule group is named identically to a controller class/function it
will be used automatically when the run() function is invoked from that
class/function.

***************************
Using Arrays as Field Names
***************************

The Form Validation class supports the use of arrays as field names.
Consider this example::

	<input type="text" name="options[]" value="" size="50" />

If you do use an array as a field name, you must use the EXACT array
name in the `Helper Functions <#helperreference>`_ that require the
field name, and as your Validation Rule field name.

For example, to set a rule for the above field you would use::

	$this->form_validation->set_rules('options[]', 'Options', 'required');

Or, to show an error for the above field you would use::

	<?php echo form_error('options[]'); ?>

Or to re-populate the field you would use::

	<input type="text" name="options[]" value="<?php echo set_value('options[]'); ?>" size="50" />

You can use multidimensional arrays as field names as well. For example::

	<input type="text" name="options[size]" value="" size="50" />

Or even::

	<input type="text" name="sports[nba][basketball]" value="" size="50" />

As with our first example, you must use the exact array name in the
helper functions::

	<?php echo form_error('sports[nba][basketball]'); ?>

If you are using checkboxes (or other fields) that have multiple
options, don't forget to leave an empty bracket after each option, so
that all selections will be added to the POST array::

	 <input type="checkbox" name="options[]" value="red" /> <input type="checkbox" name="options[]" value="blue" /> <input type="checkbox" name="options[]" value="green" />

Or if you use a multidimensional array::

	 <input type="checkbox" name="options[color][]" value="red" /> <input type="checkbox" name="options[color][]" value="blue" /> <input type="checkbox" name="options[color][]" value="green" />

When you use a helper function you'll include the bracket as well::

	<?php echo form_error('options[color][]'); ?>


**************
Rule Reference
**************

The following is a list of all the native rules that are available to
use:

Rule
Parameter
Description
Example
**required**
No
Returns FALSE if the form element is empty.
**matches**
Yes
Returns FALSE if the form element does not match the one in the
parameter.
matches[form_item]
**is_unique**
Yes
Returns FALSE if the form element is not unique to the table and field
name in the parameter.
is_unique[table.field]
**min_length**
Yes
Returns FALSE if the form element is shorter then the parameter value.
min_length[6]
**max_length**
Yes
Returns FALSE if the form element is longer then the parameter value.
max_length[12]
**exact_length**
Yes
Returns FALSE if the form element is not exactly the parameter value.
exact_length[8]
**greater_than**
Yes
Returns FALSE if the form element is less than the parameter value or
not numeric.
greater_than[8]
**less_than**
Yes
Returns FALSE if the form element is greater than the parameter value or
not numeric.
less_than[8]
**alpha**
No
Returns FALSE if the form element contains anything other than
alphabetical characters.
**alpha_numeric**
No
Returns FALSE if the form element contains anything other than
alpha-numeric characters.
**alpha_dash**
No
Returns FALSE if the form element contains anything other than
alpha-numeric characters, underscores or dashes.
**numeric**
No
Returns FALSE if the form element contains anything other than numeric
characters.
**integer**
No
Returns FALSE if the form element contains anything other than an
integer.
**decimal**
Yes
Returns FALSE if the form element is not exactly the parameter value.
**is_natural**
No
Returns FALSE if the form element contains anything other than a natural
number: 0, 1, 2, 3, etc.
**is_natural_no_zero**
No
Returns FALSE if the form element contains anything other than a natural
number, but not zero: 1, 2, 3, etc.
**is_unique**
Yes
Returns FALSE if the form element is not unique in a database table.
is_unique[table.field]
**valid_email**
No
Returns FALSE if the form element does not contain a valid email
address.
**valid_emails**
No
Returns FALSE if any value provided in a comma separated list is not a
valid email.
**valid_ip**
No
Returns FALSE if the supplied IP is not valid.
**valid_base64**
No
Returns FALSE if the supplied string contains anything other than valid
Base64 characters.

.. note:: These rules can also be called as discrete functions. For
	example::

		$this->form_validation->required($string);

.. note:: You can also use any native PHP functions that permit one
	parameter.

******************
Prepping Reference
******************

The following is a list of all the prepping functions that are available
to use:

Name
Parameter
Description
**xss_clean**
No
Runs the data through the XSS filtering function, described in the
:doc:`Input Class <input>` page.
**prep_for_form**
No
Converts special characters so that HTML data can be shown in a form
field without breaking it.
**prep_url**
No
Adds "http://" to URLs if missing.
**strip_image_tags**
No
Strips the HTML from image tags leaving the raw URL.
**encode_php_tags**
No
Converts PHP tags to entities.

.. note:: You can also use any native PHP functions that permit one
	parameter, like trim, htmlspecialchars, urldecode, etc.

******************
Function Reference
******************

The following functions are intended for use in your controller
functions.

$this->form_validation->set_rules();
======================================

Permits you to set validation rules, as described in the tutorial
sections above:

-  `Setting Validation Rules <#validationrules>`_
-  `Saving Groups of Validation Rules to a Config
   File <#savingtoconfig>`_

$this->form_validation->run();
===============================

Runs the validation routines. Returns boolean TRUE on success and FALSE
on failure. You can optionally pass the name of the validation group via
the function, as described in: `Saving Groups of Validation Rules to a
Config File <#savingtoconfig>`_.

$this->form_validation->set_message();
========================================

Permits you to set custom error messages. See `Setting Error
Messages <#settingerrors>`_ above.

****************
Helper Reference
****************

The following helper functions are available for use in the view files
containing your forms. Note that these are procedural functions, so they
**do not** require you to prepend them with $this->form_validation.

form_error()
=============

Shows an individual error message associated with the field name
supplied to the function. Example::

	<?php echo form_error('username'); ?>

The error delimiters can be optionally specified. See the `Changing the
Error Delimiters <#errordelimiters>`_ section above.

validation_errors()
====================

Shows all error messages as a string: Example::

	<?php echo validation_errors(); ?>

The error delimiters can be optionally specified. See the `Changing the
Error Delimiters <#errordelimiters>`_ section above.

set_value()
============

Permits you to set the value of an input form or textarea. You must
supply the field name via the first parameter of the function. The
second (optional) parameter allows you to set a default value for the
form. Example::

	<input type="text" name="quantity" value="<?php echo set_value('quantity', '0'); ?>" size="50" />

The above form will show "0" when loaded for the first time.

set_select()
=============

If you use a <select> menu, this function permits you to display the
menu item that was selected. The first parameter must contain the name
of the select menu, the second parameter must contain the value of each
item, and the third (optional) parameter lets you set an item as the
default (use boolean TRUE/FALSE).

Example::

	 <select name="myselect"> <option value="one" <?php echo  set_select('myselect', 'one', TRUE); ?> >One</option> <option value="two" <?php echo  set_select('myselect', 'two'); ?> >Two</option> <option value="three" <?php echo  set_select('myselect', 'three'); ?> >Three</option> </select>

set_checkbox()
===============

Permits you to display a checkbox in the state it was submitted. The
first parameter must contain the name of the checkbox, the second
parameter must contain its value, and the third (optional) parameter
lets you set an item as the default (use boolean TRUE/FALSE). Example::

	<input type="checkbox" name="mycheck[]" value="1" <?php echo set_checkbox('mycheck[]', '1'); ?> /> <input type="checkbox" name="mycheck[]" value="2" <?php echo set_checkbox('mycheck[]', '2'); ?> />

set_radio()
============

Permits you to display radio buttons in the state they were submitted.
This function is identical to the **set_checkbox()** function above.

::

	<input type="radio" name="myradio" value="1" <?php echo  set_radio('myradio', '1', TRUE); ?> /> <input type="radio" name="myradio" value="2" <?php echo  set_radio('myradio', '2'); ?> />