Blame - user_guide/libraries/form_validation.html - code-igniter-v3-giggi

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<h1>Form Validation</h1>

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

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<p class="important"><strong>Note:</strong>  As of CodeIgniter 1.6.4, this Form Validation class supercedes the old Validation class, which is now deprecated. We

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have left the old class in the library so applications currently using it will not break, but you are encouraged to migrate to this new version.</p>

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<ul>

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<li><a href="#overview">Overview</a></li>

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<li><a href="#tutorial">Form Validation Tutorial</a>

<ul>

<li><a href="#thesuccesspage">The Success Page</a></li>

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<li><a href="#thecontroller">The Controller</a></li>

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<li><a href="#validationrules">Setting Validation Rules</a></li>

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<li><a href="#validationrulesasarray">Setting Validation Rules Using an Array</a></li>

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<li><a href="#cascadingrules">Cascading Rules</a></li>

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<li><a href="#preppingdata">Prepping Data</a></li>

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<li><a href="#repopulatingform">Re-populating the Form</a></li>

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<li><a href="#callbacks">Callbacks</a></li>

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<li><a href="#settingerrors">Setting Error Messages</a></li>

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<li><a href="#errordelimiters">Changing the Error Delimiters</a></li>

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<li><a href="#individualerrors">Showing Errors Individually</a></li>

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<li><a href="#savingtoconfig">Saving Sets of Validation Rules to a Config File</a></li>

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</ul>

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</li>

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<li><a href="#rulereference">Rule Reference</a></li>

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<li><a href="#preppingreference">Prepping Reference</a></li>

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<li><a href="#functionreference">Function Reference</a></li>

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<li><a href="#helperreference">Helper Reference</a></li>

</ul>

<h1>Overview</h1>

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

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<ol>

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<li>A form is displayed.</li>

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<li>You fill it in and submit it.</li>

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<li>If you submitted something invalid, or perhaps missed a required item, the form is redisplayed containing your data

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along with an error message describing the problem.</li>

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<li>This process continues until you have submitted a valid form.</li>

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</ol>

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<p>On the receiving end, the script must:</p>

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<ol>

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<li>Check for required data.</li>

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<li>Verify that the data is of the correct type, and meets the correct criteria. For example, if a username is submitted

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it must be validated to contain only permitted characters. It must be of a minimum length,

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and not exceed a maximum length. The username can't be someone else's existing username, or perhaps even a reserved word. Etc.</li>

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<li>Sanitize the data for security.</li>

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<li>Pre-format the data if needed (Does the data need to be trimmed? HTML encoded? Etc.)</li>

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<li>Prep the data for insertion in the database.</li>

</ol>

<p>Although there is nothing terribly complex about the above process, it usually requires a significant

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amount of code, and to display error messages, various control structures are usually placed within the form HTML.

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Form validation, while simple to create, is generally very messy and tedious to implement.</p>

<h1>Form Validation Tutorial</h1>

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<p>What follows is a "hands on" tutorial for implementing CodeIgniters Form Validation.</p>

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<p>In order to implement form validation you'll need three things:</p>

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<ol>

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<li>A <a href="../general/views.html">View</a> file containing a form.</li>

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<li>A View file containing a "success" message to be displayed upon successful submission.</li>

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<li>A <a href="../general/controllers.html">controller</a> function to receive and process the submitted data.</li>

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</ol>

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

<p>Using a text editor, create a form called <dfn>myform.php</dfn>. In it, place this code and save it to your <samp>applications/views/</samp>

folder:</p>

<head>

</head>

<body>

<?php echo validation_errors(); ?>

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<?php echo form_open('form'); ?>

<h5>Username</h5>

<h5>Password</h5>

<h5>Password Confirm</h5>

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<h5>Email Address</h5>

</form>

</body>

</html>

</textarea>

<h2>The Success Page</h2>

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<p>Using a text editor, create a form called <dfn>formsuccess.php</dfn>. In it, place this code and save it to your <samp>applications/views/</samp>

folder:</p>

<html>

<head>

</head>

<body>

<h3>Your form was successfully submitted!</h3>

</body>

</html>

</textarea>

<h2>The Controller</h2>

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<p>Using a text editor, create a controller called <dfn>form.php</dfn>. In it, place this code and save it to your <samp>applications/controllers/</samp>

folder:</p>

<textarea class="textarea" style="width:100%" cols="50" rows="21"><?php

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class Form extends Controller {

function index()

{

$this->load->helper(array('form', 'url'));

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

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if ($this->form_validation->run() == FALSE)

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{

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$this->load->view('myform');

}

else

{

$this->load->view('formsuccess');

}

}

}

?></textarea>

<p>To try your form, visit your site using a URL similar to this one:</p>

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<code>example.com/index.php/<var>form</var>/</code>

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<p><dfn>If you submit the form you should simply see the form reload. That's because you haven't set up any validation

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rules yet.</dfn></p>

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<p><strong>Since you haven't told the Form Validation class to validate anything yet, it returns <kbd>FALSE</kbd> (boolean false) by default. The <samp>run()</samp>

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function only returns <kbd>TRUE</kbd> if it has successfully applied your rules without any of them failing.</strong></p>

<h2>Explanation</h2>

<p>You'll notice several things about the above pages:</p>

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<p>The <dfn>form</dfn> (myform.php) is a standard web form with a couple exceptions:</p>

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<ol>

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<li>It uses a <dfn>form helper</dfn> to create the form opening.

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Technically, this isn't necessary. You could create the form using standard HTML. However, the benefit of using the helper

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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.</li>

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<li>At the top of the form you'll notice the following function call:

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

</li>

</ol>

<p>The <dfn>controller</dfn> (form.php) has one function: <dfn>index()</dfn>. This function initializes the validation class and

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loads the <var>form helper</var> and <var>URL helper</var> used by your view files. It also <samp>runs</samp>

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the validation routine. Based on

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whether the validation was successful it either presents the form or the success page.</p>

<h2>Setting Validation Rules</h2>

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<p>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

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at the same time. To set validation rules you will use the <dfn>set_rules()</dfn> function:</p>

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<code>$this->form_validation->set_rules();</code>

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<p>The above function takes <srong>three</strong> parameters as input:</p>

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<ol>

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<li>The field name - the exact name you've given the form field.</li>

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<li>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".</li>

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<li>The validation rules for this form field.</li>

</ol>

<p><br />Here is an example. In your <dfn>controller</dfn> (form.php), add this code just below the validation initialization function:</p>

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<code>

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$this->form_validation->set_rules('username', 'Username', 'required');<br />

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$this->form_validation->set_rules('password', 'Password', 'required');<br />

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$this->form_validation->set_rules('passconf', 'Password Confirmation', 'required');<br />

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$this->form_validation->set_rules('email', 'Email', 'required');<br />

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</code>

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<p>Your controller should now look like this:</p>

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<textarea class="textarea" style="width:100%" cols="50" rows="28"><?php

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class Form extends Controller {

function index()

{

$this->load->helper(array('form', 'url'));

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

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

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$this->form_validation->set_rules('password', 'Password', 'required');

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$this->form_validation->set_rules('passconf', 'Password Confirmation', 'required');

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$this->form_validation->set_rules('email', 'Email', 'required');

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if ($this->form_validation->run() == FALSE)

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{

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$this->load->view('myform');

}

else

{

$this->load->view('formsuccess');

}

}

}

?></textarea>

<p><dfn>Now submit the form with the fields blank and you should see the error messages.

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If you submit the form with all the fields populated you'll see your success page.</dfn></p>

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<p class="important"><strong>Note:</strong> The form fields are not yet being re-populated with the data when

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there is an error. We'll get to that shortly.</p>

<h2>Setting Rules Using an Array</h2>

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<p>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.

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If you use this approach you must name your array keys as indicated:</p>

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<code>

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$config = array(<br />

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               array(<br />

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                     'field'   => 'username', <br />

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                     'label'   => 'Username', <br />

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                     'rules'   => 'required'<br />

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                  ),<br />

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               array(<br />

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                     'field'   => 'password', <br />

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                     'label'   => 'Password', <br />

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                     'rules'   => 'required'<br />

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                  ),<br />

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               array(<br />

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                     'field'   => 'passconf', <br />

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                     'label'   => 'Password Confirmation', <br />

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                     'rules'   => 'required'<br />

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                  ),   <br />

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               array(<br />

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                     'field'   => 'email', <br />

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                     'label'   => 'Email', <br />

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                     'rules'   => 'required'<br />

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                  )<br />

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            );<br />

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<br />

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

</code>

<h2>Cascading Rules</h2>

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

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<code>

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$this->form_validation->set_rules('username', 'Username', 'required|min_length[5]|max_length[12]');<br />

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$this->form_validation->set_rules('password', 'Password', 'required|matches[passconf]');<br />

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$this->form_validation->set_rules('passconf', 'Password Confirmation', 'required');<br />

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$this->form_validation->set_rules('email', 'Email', 'required|valid_email');<br />

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</code>

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<p>The above code sets the following rules:</p>

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<ol>

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<li>The username field be no shorter than 5 characters and no longer than 12.</li>

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<li>The password field must match the password confirmation field.</li>

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<li>The email field must contain a valid email address.</li>

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</ol>

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<p>Give it a try! Submit your form without the proper data and you'll see new error messages that correspond to your new rules.

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There are numerous rules available which you can read about in the validation reference.</p>

<h2>Prepping Data</h2>

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<p>In addition to the validation functions like the ones we used above, you can also prep your data in various ways.

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For example, you can set up rules like this:</p>

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<code>

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$this->form_validation->set_rules('username', 'Username', '<kbd>trim</kbd>|required|min_length[5]|max_length[12]|<kbd>xss_clean</kbd>');<br />

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$this->form_validation->set_rules('password', 'Password', '<kbd>trim</kbd>|required|matches[passconf]|<kbd>md5</kbd>');<br />

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$this->form_validation->set_rules('passconf', 'Password Confirmation', '<kbd>trim</kbd>|required');<br />

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$this->form_validation->set_rules('email', 'Email', '<kbd>trim</kbd>|required|valid_email');<br />

</code>

<p>In the above example, we are "trimming" the fields, converting the password to MD5, and running the username through

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the "xss_clean" function, which removes malicious data.</p>

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<p><strong>Any native PHP function that accepts one parameter can be used as a rule, like <dfn>htmlspecialchars</dfn>,

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<p><strong>Note:</strong> You will generally want to use the prepping functions <strong>after</strong>

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the validation rules so if there is an error, the original data will be shown in the form.</p>

<h2>Re-populating the form</h2>

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<p>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

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that permit you to do this. The one you will use most commonly is:</p>

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<code>set_value('field name')</code>

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<p>Open your <dfn>myform.php</dfn> view file and update the <strong>value</strong> in each field using the <dfn>set_value()</dfn> function:</p>

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<p><strong>Don't forget to include each. field name in the <dfn>set_value()</dfn> functions!</strong></p>

<html>

<head>

</head>

<body>

<?php echo validation_errors(); ?>

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<?php echo form_open('form'); ?>

<h5>Username</h5>

<h5>Password</h5>

<h5>Password Confirm</h5>

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<h5>Email Address</h5>

</form>

</body>

</html>

</textarea>

<p><dfn>Now reload your page and submit the form so that it triggers an error. Your form fields should now be re-populated</dfn></p>

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<p class="important"><strong>Note:</strong> The <a href="#functionreference">Function Reference</a> section below contains functions that

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permit you to re-populate <select> menus, radio buttons, and checkboxes.</p>

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<p><strong>Important Note:</strong> If you use an array as the name of a form field, you must supply it as an array to the function. Example:</p>

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

<h2>Callbacks: Your own Validation Functions</h2>

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<p>The validation system supports callbacks to your own validation functions. This permits you to extend the validation class

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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

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create a callback function that does that. Let's create a example of this.</p>

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<p>In your controller, change the "username" rule to this:</p>

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<code>$this->form_validation->set_rules('username', 'Username', '<kbd>callback_username_check</kbd>');</code>

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<p>Then add a new function called <dfn>username_check</dfn> to your controller. Here's how your controller should now look:</p>

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<textarea class="textarea" style="width:100%" cols="50" rows="44"><?php

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class Form extends Controller {

function index()

{

$this->load->helper(array('form', 'url'));

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

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

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$this->form_validation->set_rules('password', 'Password', 'required');

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$this->form_validation->set_rules('passconf', 'Password Confirmation', 'required');

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$this->form_validation->set_rules('email', 'Email', 'required');

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if ($this->form_validation->run() == FALSE)

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{

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$this->load->view('myform');

}

else

{

$this->load->view('formsuccess');

}

}

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;

}

}

}

?></textarea>

<p><dfn>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

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callback function for you to process.</dfn></p>

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<p><strong>To invoke a callback just put the function name in a rule, with "callback_" as the rule prefix.</strong></p>

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<p>You can also process the form data that is passed to your callback and return it. If your callback returns anything other then a boolean TRUE/FALSE

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it is assumed that the data is your newly processed form data.</p>

<h2>Setting Error Messages</h2>

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

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

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<code>$this->form_validation->set_message('<var>rule</var>', '<var>Error Message</var>');</code>

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

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

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

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<code>$this->form_validation->set_message('username_check')</code>

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

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

<h2>Changing the Error Delimiters</h2>

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<p>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.</p>

<ol>

<li><strong>Changing delimiters Globally</strong>

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<p>To globally change the error delimiters, in your controller function, just after loading the Form Validation class, add this:</p>

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<code><?php echo $this->form_validation->set_error_delimiters('<kbd><div class="error"></kbd>', '<kbd></div></kbd>');</code>

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<p>In this example, we've switched to using div tags.</p>

</li>

<li><strong>Changing delimiters Individually</strong></p>

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<p>Each of the two error generating functions shown in this tutorial can be supplied their own delimiters as follows:</p>

</p>Or:</p>

</li>

</ol>

<h2>Showing Errors Individually</h2>

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

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<p>Try it! Change your form so that it looks like this:</p>

<h5>Username</h5>

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

<h5>Password</h5>

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

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<h5>Password Confirm</h5>

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

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<h5>Email Address</h5>

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

</textarea>

<p>If there are no errors, nothing will be shown. If there is an error, the message will appear.</p>

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<p><strong>Important Note:</strong> If you use an array as the name of a form field, you must supply it as an array to the function. Example:</p>

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<code><?php echo form_error('<kbd>options[size]</kbd>'); ?><br />

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

</code>

<h1>Saving Sets of Validation Rules to a Config File</h1>

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<p>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

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can organize these rules into "groups". These groups can either be loaded automatically when a matching controller/function is called, or

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you can manually call each set as needed.</p>

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<h3>How to save your rules</h3>

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<p>To store your validation rules, simply create a file named <kbd>form_validation.php</kbd> in your <dfn>application/config/</dfn> folder.

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In that file you will place an array named <kbd>$config</kbd> with your rules. As shown earlier, the validation array will have this prototype:</p>

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<code>

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$config = array(<br />

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               array(<br />

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                     'field'   => 'username', <br />

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                     'label'   => 'Username', <br />

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                     'rules'   => 'required'<br />

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                  ),<br />

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               array(<br />

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                     'field'   => 'password', <br />

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                     'label'   => 'Password', <br />

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                     'rules'   => 'required'<br />

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                  ),<br />

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               array(<br />

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                     'field'   => 'passconf', <br />

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                     'label'   => 'Password Confirmation', <br />

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                     'rules'   => 'required'<br />

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                  ),   <br />

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               array(<br />

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                     'field'   => 'email', <br />

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                     'label'   => 'Email', <br />

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                     'rules'   => 'required'<br />

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                  )<br />

            );<br />

</code>

<p><dfn>Your validation rule file will be loaded automatically and used when you call the run() function.</dfn></p>

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<p class="important">Please note that you MUST name your array $config.</p>

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<h3>Creating Sets of Rules</h3>

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<p>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.

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We've arbitrarily called these two rules "signup" and "email". You can name your rules anything you want:</p>

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<code>$config = array(<br />

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                 '<kbd>signup</kbd>' = array(<br />

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                                    array(<br />

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                                            'field' => 'username',<br />

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                                            'label' => 'Username',<br />

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                                            'rules' => 'required'<br />

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                                         ),<br />

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                                    array(<br />

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                                            'field' => 'password',<br />

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                                            'label' => 'Password',<br />

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                                            'rules' => 'required'<br />

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                                         ),<br />

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                                    array(<br />

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                                            'field' => 'passconf',<br />

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                                            'label' => 'PasswordConfirmation',<br />

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                                            'rules' => 'required'<br />

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                                         ),<br />

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                                    array(<br />

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                                            'field' => 'email',<br />

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                                            'label' => 'Email',<br />

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                                            'rules' => 'required'<br />

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                                         )<br />

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                                    ),<br />

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                 '<kbd>email</kbd>' = array(<br />

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                                    array(<br />

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                                            'field' => 'emailaddress',<br />

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                                            'label' => 'EmailAddress',<br />

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                                            'rules' => 'required|valid_email'<br />

739

                                         ),<br />

740

                                    array(<br />

741

                                            'field' => 'name',<br />

742

                                            'label' => 'Name',<br />

743

                                            'rules' => 'required|alpha'<br />

744

                                         ),<br />

745

                                    array(<br />

746

                                            'field' => 'title',<br />

747

                                            'label' => 'Title',<br />

748

                                            'rules' => 'required'<br />

749

                                         ),<br />

750

                                    array(<br />

751

                                            'field' => 'message',<br />

752

                                            'label' => 'MessageBody',<br />

753

                                            'rules' => 'required'<br />

754

                                         )<br />

755

                                    )                          <br />

756

               );<br />

</code>

<h3>Calling a Specific Rule Group</h3>

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762

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

763

764

<code>

765

if ($this->form_validation->run('<kbd>signup</kbd>') == FALSE)<br />

766

{<br />

767

   $this->load->view('myform');<br />

}<br />

else<br />

{<br />

   $this->load->view('formsuccess');<br />

}<br />

</code>

<h3>Associating a Controller Function with a Rule Group</h3>

778

779

<p>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

780

have a controller named <kbd>Member</kbd> and a function named <kbd>signup</kbd>. Here's what your class might look like:</p>

<code>

<?php<br /><br />

class <kbd>Member</kbd> extends Controller {<br />

785

<br />

786

   function <kbd>signup</kbd>()<br />

787

   {      <br />

788

      $this->load->library('form_validation');<br />

789

            <br />

790

      if ($this->form_validation->run() == FALSE)<br />

791

      {<br />

792

         $this->load->view('myform');<br />

      }<br />

      else<br />

      {<br />

         $this->load->view('formsuccess');<br />

      }<br />

   }<br />

}<br />

?></code>

<p>In your validation config file, you will name your rule group <kbd>member/signup</kbd>:

803

804

805

<code>$config = array(<br />

806

           '<kbd>member/signup</kbd>' = array(<br />

807

                                    array(<br />

808

                                            'field' => 'username',<br />

809

                                            'label' => 'Username',<br />

810

                                            'rules' => 'required'<br />

811

                                         ),<br />

812

                                    array(<br />

813

                                            'field' => 'password',<br />

814

                                            'label' => 'Password',<br />

815

                                            'rules' => 'required'<br />

816

                                         ),<br />

817

                                    array(<br />

818

                                            'field' => 'passconf',<br />

819

                                            'label' => 'PasswordConfirmation',<br />

820

                                            'rules' => 'required'<br />

821

                                         ),<br />

822

                                    array(<br />

823

                                            'field' => 'email',<br />

824

                                            'label' => 'Email',<br />

825

                                            'rules' => 'required'<br />

826

                                         )<br />

827

                                    )<br />

828

               );<br />

829

</code>

830

831

<p><dfn>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.</dfn></p>

<h1>Rule Reference</h1>

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

<tr>

<th>Parameter</th>

<th>Description</th>

<th>Example</th>

</tr><tr>

<td class="td"><strong>required</strong></td>

859

860

<td class="td">Returns FALSE if the form element is empty.</td>

</tr><tr>

<td class="td"><strong>matches</strong></td>

865

866

<td class="td">Returns FALSE if the form element does not match the one in the parameter.</td>

867

<td class="td">matches[form_item]</td>

868

</tr><tr>

869

870

<td class="td"><strong>min_length</strong></td>

871

872

<td class="td">Returns FALSE if the form element is shorter then the parameter value.</td>

873

<td class="td">min_length[6]</td>

874

</tr><tr>

875

876

<td class="td"><strong>max_length</strong></td>

877

878

<td class="td">Returns FALSE if the form element is longer then the parameter value.</td>

879

<td class="td">max_length[12]</td>

880

</tr><tr>

881

882

<td class="td"><strong>exact_length</strong></td>

883

884

<td class="td">Returns FALSE if the form element is not exactly the parameter value.</td>

885

<td class="td">exact_length[8]</td>

886

</tr><tr>

887

888

<td class="td"><strong>alpha</strong></td>

889

890

<td class="td">Returns FALSE if the form element contains anything other than alphabetical characters.</td>

</tr><tr>

<td class="td"><strong>alpha_numeric</strong></td>

895

896

<td class="td">Returns FALSE if the form element contains anything other than alpha-numeric characters.</td>

</tr><tr>

<td class="td"><strong>alpha_dash</strong></td>

901

902

<td class="td">Returns FALSE if the form element contains anything other than alpha-numeric characters, underscores or dashes.</td>

</tr>

<tr>

<td class="td"><strong>numeric</strong></td>

908

909

<td class="td">Returns FALSE if the form element contains anything other than numeric characters.</td>

</tr>

<tr>

<td class="td"><strong>integer</strong></td>

915

916

<td class="td">Returns FALSE if the form element contains anything other than an integer.</td>

</tr>

<tr>

<td class="td"><strong>is_natural</strong></td>

922

923

<td class="td">Returns FALSE if the form element contains anything other than a natural number: 0, 1, 2, 3, etc.</td>

</tr>

<tr>

<td class="td"><strong>is_natural_no_zero</strong></td>

929

930

<td class="td">Returns FALSE if the form element contains anything other than a natural number, but not zero: 1, 2, 3, etc.</td>

</tr>

<tr>

<td class="td"><strong>valid_email</strong></td>

936

937

<td class="td">Returns FALSE if the form element does not contain a valid email address.</td>

</tr>

<tr>

<td class="td"><strong>valid_emails</strong></td>

943

944

<td class="td">Returns FALSE if any value provided in a comma separated list is not a valid email.</td>

</tr>

<tr>

<td class="td"><strong>valid_ip</strong></td>

950

951

<td class="td">Returns FALSE if the supplied IP is not valid.</td>

</tr>

<tr>

<td class="td"><strong>valid_base64</strong></td>

957

958

<td class="td">Returns FALSE if the supplied string contains anything other than valid Base64 characters.</td>

</tr>

</table>

<p><strong>Note:</strong> These rules can also be called as discrete functions. For example:</p>

966

967

<code>$this->form_validation->required($string);</code>

968

969

<p class="important"><strong>Note:</strong> You can also use any native PHP functions that permit one parameter.</p>

<h1>Prepping Reference</h1>

977

978

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

<tr>

<th>Parameter</th>

<th>Description</th>

</tr><tr>

<td class="td"><strong>xss_clean</strong></td>

990

991

<td class="td">Runs the data through the XSS filtering function, described in the <a href="input.html">Input Class</a> page.</td>

</tr><tr>

<td class="td">Converts special characters so that HTML data can be shown in a form field without breaking it.</td>

</tr><tr>

<td class="td">Adds "http://" to URLs if missing.</td>

1002

</tr><tr>

1003

1004

<td class="td"><strong>strip_image_tags</strong></td>

1005

1006

<td class="td">Strips the HTML from image tags leaving the raw URL.</td>

1007

</tr><tr>

1008

1009

<td class="td"><strong>encode_php_tags</strong></td>

1010

1011

<td class="td">Converts PHP tags to entities.</td>

</tr>

</table>

<p class="important"><strong>Note:</strong> You can also use any native PHP functions that permit one parameter,

1017

like <kbd>trim</kbd>, <kbd>htmlspecialchars</kbd>, <kbd>urldecode</kbd>, etc.</p>

<h1>Function Reference</h1>

1029

1030

<h2>$this->form_validation->set_rule();</h2>

1031

1032

<p>Permits you to set validation rules, as described in the tutorial sections above:</p>

1033

1034

<ul>

1035

<li><a href="#validationrules">Setting Validation Rules</a></li>

1036

<li><a href="#savingtoconfig">Saving Groups of Validation Rules to a Config File</a></li>

</ul>

<h2>$this->form_validation->run();</h2>

1041

1042

<p>Runs the validation routines. Returns boolean TRUE on success and FALSE on failure. You can optionally pass the name of the validation

1043

group via the function, as described in: <a href="#savingtoconfig">Saving Groups of Validation Rules to a Config File</a>.</p>

1044

1045

1046

<h2>$this->form_validation->set_message();</h2>

1047

1048

<p>Permits you to set custom error messages. See <a href="#settingerrors">Setting Error Messages</a> above.</p>

<h1>Helper Reference</h1>

1055

1056

<p>The following helper functions are available for use in the view files containing your forms. Note that these are procedural functions, so they

1057

<strong>do not</strong> require you to prepend them with $this->form_validation.</p>

1058

1059

<h2>form_error()</h2>

1060

1061

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

<p>The error delimiters can be optionally specified. See the <a href="#errordelimiters">Changing the Error Delimiters</a> section above.</p>

<h2>validation_errors()</h2>

1070

<p>Shows all error messages as a string: Example:</p>

<p>The error delimiters can be optionally specified. See the <a href="#errordelimiters">Changing the Error Delimiters</a> section above.</p>

<h2>set_value()</h2>

<p>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.

1081

The second (optional) parameter allows you to set a default value for the form. Example:</p>

<p>The above form will show "0" when loaded for the firs time.</p>

1086

1087

<h2>set_select()</h2>

1088

1089

<p>If you use a <dfn><select></dfn> menu, this function permits you to display the menu item that was selected. The first parameter

1090

must contain the name of the select menu, the second parameter must contain the value of

1091

each item, and the third (optional) parameter lets you set an item as the default (use boolean TRUE/FALSE).</p>

<p>Example:</p>

<code>

<option value="three" <dfn><?php echo set_select('myselect', 'three'); ?></dfn> >Three</option><br />

</select>

</code>

<h2>set_checkbox()</h2>

1105

1106

<p>Permits you to display a checkbox in the state it was submitted. The first parameter

1107

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:</p>

<h2>set_radio()</h2>

<p>Permits you to display radio buttons in the state they were submitted. This function is identical to the <strong>set_checkbox()</strong> function above.</p>