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diff --git a/user_guide/libraries/validation.html b/user_guide/libraries/validation.html new file mode 100644 index 000000000..2489aa6e9 --- /dev/null +++ b/user_guide/libraries/validation.html @@ -0,0 +1,674 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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+<div id="masthead">
+<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
+<tr>
+<td><h1>Code Igniter User Guide Version 1.4.0</h1></td>
+<td id="breadcrumb_right"><a href="../toc.html">Full Table of Contents</a></td>
+</tr>
+</table>
+</div>
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+<td id="breadcrumb">
+<a href="http://www.codeigniter.com/">Code Igniter Home</a> ›
+<a href="../index.html">User Guide Home</a> ›
+Form Validation
+</td>
+<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="www.codeigniter.com/user_guide/" />Search User Guide <input type="text" class="input" style="width:200px;" name="q" id="q" size="31" maxlength="255" value="" /> <input type="submit" class="submit" name="sa" value="Go" /></form></td>
+</tr>
+</table>
+<!-- END BREADCRUMB -->
+
+<br clear="all" />
+
+
+<!-- START CONTENT -->
+<div id="content">
+
+<h1>Form Validation</h1>
+
+<p>Before explaining Code Igniter's approach to data validation, let's describe the ideal scenario:</p>
+
+<ol>
+<li>A form is displayed.</li>
+<li>You fill it in and submit it.</li>
+<li>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.</li>
+<li>This process continues until you have submitted a valid form.</li>
+</ol>
+
+<p>On the receiving end, the script must:</p>
+
+<ol>
+<li>Check for required data.</li>
+<li>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.)
+<li>Sanitize the data for security.</li>
+<li>Pre-format the data if needed (Does the data need to be trimmed? HTML encoded? Etc.)</li>
+<li>Prep the data for insertion in the database.</li>
+</ol>
+
+
+<p>Although there is nothing 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.</p>
+
+<dfn>Code Igniter provides a comprehensive validation framework that truly minimizes the amount of code you'll write.
+It also removes all control structures from your form HTML, permitting it to be clean and free of code.</dfn>
+
+<h2>Overview</h2>
+
+<p>In order to implement Code Igniter's form validation you'll need three things:</p>
+
+<ol>
+<li>A <a href="../general/views.html">View</a> file containing the form.</li>
+<li>A View file containing a "success" message to be displayed upon successful submission.</li>
+<li>A <a href="../general/controllers.html">controller</a> function to receive and process the submitted data.</li>
+</ol>
+
+<p>Let's create those three things, using a member sign-up form as the example.</p>
+
+<h2>The Form</h2>
+
+<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>
+
+
+<textarea class="textarea" style="width:100%" cols="50" rows="30"><html>
+<head>
+<title>My Form</title>
+</head>
+<body>
+
+<?=$this->validation->error_string; ?>
+
+<?=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></textarea>
+
+
+<h2>The Success Page</h2>
+
+
+<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>
+
+
+<textarea class="textarea" style="width:100%" cols="50" rows="14"><html>
+<head>
+<title>My Form</title>
+</head>
+<body>
+
+<h3>Your form was successfully submitted!</h3>
+
+<p><?=anchor('form', 'Try it again!'); ?></p>
+
+</body>
+</html></textarea>
+
+
+<h2>The Controller</h2>
+
+<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
+
+class Form extends Controller {
+
+ function index()
+ {
+ $this->load->helper(array('form', 'url'));
+
+ $this->load->library('validation');
+
+ if ($this->validation->run() == FALSE)
+ {
+ $this->load->view('myform');
+ }
+ else
+ {
+ $this->load->view('formsuccess');
+ }
+ }
+}
+?></textarea>
+
+
+<h2>Try it!</h2>
+
+<p>To try your form, visit your site using a URL similar to this one:</p>
+
+<code>www.your-site.com/index.php/<var>form</var>/</code>
+
+<p><strong>If you submit the form you should simply see the form reload. That's because you haven't set up any validation
+rules yet, which we'll get to in a moment.</strong></p>
+
+
+<h2>Explanation</h2>
+
+<p>You'll notice several things about the above pages:</p>
+
+<p>The <dfn>form</dfn> (myform.php) is a standard web form with a couple exceptions:</p>
+
+<ol>
+<li>It uses a <dfn>form helper</dfn> to create the form opening.
+Technically, this isn't necessary. You could create the form using standard HTML. However, the benefit of using the helper
+is that it generates the action URL for you, based on the URL in your config file. This makes your application more portable
+and flexible in the event your URLs change.</li>
+
+<li>At the top of the form you'll notice the following variable:
+<code><?=$this->validation->error_string; ?></code>
+
+<p>This variable will display any error messages sent back by the validator. If there are no messages it returns nothing.</p>
+</li>
+</ol>
+
+<p>The <dfn>controller</dfn> (form.php) has one function: <dfn>index()</dfn>. This function initializes the validation class and
+loads the <var>form helper</var> and <var>URL helper</var> used by your view files. It also <samp>runs</samp>
+the validation routine. Based on
+whether the validation was successful it either presents the form or the success page.</p>
+
+<p><strong>Since you haven't told the validation class to validate anything yet, it returns "false" (boolean false) by default. The <samp>run()</samp>
+function only returns "true" if it has successfully applied your rules without any of them failing.</strong></p>
+
+
+<h2>Setting Validation Rules</h2>
+
+<p>Code Igniter 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. Let's see it in action, we'll explain it afterwards.</p>
+
+<p>In your <dfn>controller</dfn> (form.php), add this code just below the validation initialization function:</p>
+
+<code>$rules['username'] = "required";<br />
+$rules['password'] = "required";<br />
+$rules['passconf'] = "required";<br />
+$rules['email'] = "required";<br />
+<br />
+$this->validation->set_rules($rules);</code>
+
+<p>Your controller should now look like this:</p>
+
+<textarea class="textarea" style="width:100%" cols="50" rows="28"><?php
+
+class Form extends Controller {
+
+ function index()
+ {
+ $this->load->helper(array('form', 'url'));
+
+ $this->load->library('validation');
+
+ $rules['username'] = "required";
+ $rules['password'] = "required";
+ $rules['passconf'] = "required";
+ $rules['email'] = "required";
+
+ $this->validation->set_rules($rules);
+
+ if ($this->validation->run() == FALSE)
+ {
+ $this->load->view('myform');
+ }
+ else
+ {
+ $this->load->view('formsuccess');
+ }
+ }
+}
+?></textarea>
+
+<p><dfn>Now submit the form with the fields blank and you should see the error message.
+If you submit the form with all the fields populated you'll see your success page.</dfn></p>
+
+<p class="important"><strong>Note:</strong> The form fields are not yet being re-populated with the data when
+there is an error. We'll get to that shortly, once we're through explaining the validation rules.</p>
+
+
+<h2>Changing the Error Delimiters</h2>
+
+<p>By default, the system adds a paragraph tag (<p>) around each error message shown. You can easily change these delimiters with
+this code, placed in your controller:</p>
+
+<code>$this->validation->set_error_delimiters('<kbd><div class="error"></kbd>', '<kbd></div></kbd>');</code>
+
+<p>In this example, we've switched to using div tags.</p>
+
+<h2>Cascading Rules</h2>
+
+<p>Code Igniter lets you pipe multiple rules together. Let's try it. Change your rules array like this:</p>
+
+
+<code>$rules['username'] = "required|min_length[5]|max_length[12]";<br />
+$rules['password'] = "required|matches[passconf]";<br />
+$rules['passconf'] = "required";<br />
+$rules['email'] = "required|valid_email";</code>
+
+<p>The above code requires that:</p>
+
+<ol>
+<li>The username field be no shorter than 5 characters and no longer than 12.</li>
+<li>The password field must match the password confirmation field.</li>
+<li>The email field must contain a valid email address.</li>
+</ol>
+
+<p>Give it a try!</p>
+
+<p class="important"><strong>Note:</strong> There are numerous rules available which you can read about in the validation reference.</p>
+
+
+<h2>Prepping Data</h2>
+
+<p>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:
+
+<code>$rules['username'] = "<kbd>trim</kbd>|required|min_length[5]|max_length[12]|<kbd>xss_clean</kbd>";<br />
+$rules['password'] = "<kbd>trim</kbd>|required|matches[passconf]|<kbd>md5</kbd>";<br />
+$rules['passconf'] = "<kbd>trim</kbd>|required";<br />
+$rules['email'] = "<kbd>trim</kbd>|required|valid_email";</code>
+
+<p>In the above, we are "trimming" the fields, converting the password to MD5, and running the username through
+the "xss_clean" function, which removes malicious data.</p>
+
+<p class="important"><strong>Any native PHP function that accepts one parameter can be used as a rule, like <dfn>htmlspecialchars</dfn>,
+<dfn>trim</dfn>, <dfn>MD5</dfn>, etc.</strong></p>
+
+<p><strong>Note:</strong> You will generally want to use the prepping functions <strong>after</strong>
+the validation rules so if there is an error, the original data will be shown in the form.</p>
+
+<h2>Callbacks: Your own Validation Functions</h2>
+
+<p>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 simple example.</p>
+
+<p>In your controller, change the "username" rule to this:</p>
+
+<code>$rules['username'] = "callback_username_check"; </code>
+
+<p>Then add a new function called <dfn>username_check</dfn> to your controller. Here's how your controller should look:</p>
+
+
+<textarea class="textarea" style="width:100%" cols="50" rows="44"><?php
+
+class Form extends Controller {
+
+ function index()
+ {
+ $this->load->helper(array('form', 'url'));
+
+ $this->load->library('validation');
+
+ $rules['username'] = "callback_username_check";
+ $rules['password'] = "required";
+ $rules['passconf'] = "required";
+ $rules['email'] = "required";
+
+ $this->validation->set_rules($rules);
+
+ if ($this->validation->run() == FALSE)
+ {
+ $this->load->view('myform');
+ }
+ else
+ {
+ $this->load->view('formsuccess');
+ }
+ }
+
+ function username_check($str)
+ {
+ if ($str == 'test')
+ {
+ $this->validation->set_message('username_check', 'The %s field can not be the word "test"');
+ return FALSE;
+ }
+ else
+ {
+ return TRUE;
+ }
+ }
+
+}
+?></textarea>
+
+<p>Reload your form and submit it with the word "test" as the username. You can see that the form field data was passed to your
+callback function for you to process.</p>
+
+<p><strong>To invoke a callback just put the function name in a rule, with "callback_" as the rule prefix.</strong></p>
+
+<p>The error message was set using the <dfn>$this->validation->set_message</dfn> function.
+Just remember that the message key (the first parameter) must match your function name.</p>
+
+<p class="important"><strong>Note:</strong> You can apply your own custom error messages to any rule, just by setting the
+message similarly. For example, to change the message for the "required" rule you will do this:</p>
+
+<code>$this->validation->set_message('required', 'Your custom message here');</code>
+
+<h2>Re-populating the form</h2>
+
+<p>Thus far we have only been dealing with errors. It's time to repopulate the form field with the submitted data.
+This is done similarly to your rules. Add the following code to your controller, just below your rules:</p>
+
+<code>$fields['username'] = 'Username';<br />
+$fields['password'] = 'Password';<br />
+$fields['passconf'] = 'Password Confirmation';<br />
+$fields['email'] = 'Email Address';<br />
+<br />
+$this->validation->set_fields($fields);</code>
+
+<p>The array keys are the actual names of the form fields, the value represents the full name that you want shown in the
+error message.</p>
+
+<p>The index function of your controller should now look like this:</p>
+
+
+<textarea class="textarea" style="width:100%" cols="50" rows="30">function index()
+{
+ $this->load->helper(array('form', 'url'));
+
+ $this->load->library('validation');
+
+ $rules['username'] = "required";
+ $rules['password'] = "required";
+ $rules['passconf'] = "required";
+ $rules['email'] = "required";
+
+ $this->validation->set_rules($rules);
+
+ $fields['username'] = 'Username';
+ $fields['password'] = 'Password';
+ $fields['passconf'] = 'Password Confirmation';
+ $fields['email'] = 'Email Address';
+
+ $this->validation->set_fields($fields);
+
+ if ($this->validation->run() == FALSE)
+ {
+ $this->load->view('myform');
+ }
+ else
+ {
+ $this->load->view('formsuccess');
+ }
+}</textarea>
+
+
+<p>Now open your <dfn>myform.php</dfn> view file and update the value in each field so that it has an object corresponding to its name:</p>
+
+
+<textarea class="textarea" style="width:100%" cols="50" rows="30"><html>
+<head>
+<title>My Form</title>
+</head>
+<body>
+
+<?=$this->validation->error_string; ?>
+
+<?=form_open('form'); ?>
+
+<h5>Username</h5>
+<input type="text" name="username" value="<?=$this->validation->username;?>" size="50" />
+
+<h5>Password</h5>
+<input type="text" name="password" value="<?=$this->validation->password;?>" size="50" />
+
+<h5>Password Confirm</h5>
+<input type="text" name="passconf" value="<?=$this->validation->passconf;?>" size="50" />
+
+<h5>Email Address</h5>
+<input type="text" name="email" value="<?=$this->validation->email;?>" size="50" />
+
+<div><input type="submit" value="Submit" /></div>
+
+</form>
+
+</body>
+</html></textarea>
+
+
+<p>Now reload your page and submit the form so that it triggers an error. Your form fields should be populated
+and the error messages will contain a more relevant field name.</p>
+
+
+
+<h2>Showing Errors Individually</h2>
+
+<p>If you prefer to show an error message next to each form field, rather than as a list, you can change your form so that it looks like this:</p>
+
+
+<textarea class="textarea" style="width:100%" cols="50" rows="20">
+<h5>Username</h5>
+<?=$this->validation->username_error; ?>
+<input type="text" name="username" value="<?=$this->validation->username;?>" size="50" />
+
+<h5>Password</h5>
+<?=$this->validation->password_error; ?>
+<input type="text" name="password" value="<?=$this->validation->password;?>" size="50" />
+
+<h5>Password Confirm</h5>
+<?=$this->validation->passconf_error; ?>
+<input type="text" name="passconf" value="<?=$this->validation->passconf;?>" size="50" />
+
+<h5>Email Address</h5>
+<?=$this->validation->email_error; ?>
+<input type="text" name="email" value="<?=$this->validation->email;?>" size="50" /></textarea>
+
+<p>If there are no errors, nothing will be shown. If there is an error, the message will appear, wrapped in the delimiters you
+have set (<p> tags by default).</p>
+
+<p class="important"><strong>Note: </strong>To display errors this way you must remember to set your fields using the <kbd>$this->validation->set_fields</kbd>
+function described earlier. The errors will be turned into variables that have "_error" after your field name.
+For example, your "username" error will be available at:<br /><dfn>$this->validation->username_error</dfn>.</p>
+
+
+<h2>Rule Reference</h2>
+
+<p>The following is a list of all the native rules that are available to use:</p>
+
+
+
+<table cellpadding="0" cellspacing="1" border="0" style="width:100%" class="tableborder">
+<tr>
+<th>Rule</th>
+<th>Parameter</th>
+<th>Description</th>
+<th>Example</th>
+</tr><tr>
+
+<td class="td"><strong>required</strong></td>
+<td class="td">No</td>
+<td class="td">Returns FALSE if the form element is empty.</td>
+<td class="td"> </td>
+</tr><tr>
+
+<td class="td"><strong>matches</strong></td>
+<td class="td">Yes</td>
+<td class="td">Returns FALSE if the form element does not match the one in the parameter.</td>
+<td class="td">matches[form_item]</td>
+</tr><tr>
+
+<td class="td"><strong>min_length</strong></td>
+<td class="td">Yes</td>
+<td class="td">Returns FALSE if the form element is shorter then the parameter value.</td>
+<td class="td">min_length[6]</td>
+</tr><tr>
+
+<td class="td"><strong>max_length</strong></td>
+<td class="td">Yes</td>
+<td class="td">Returns FALSE if the form element is longer then the parameter value.</td>
+<td class="td">max_length[12]</td>
+</tr><tr>
+
+<td class="td"><strong>exact_length</strong></td>
+<td class="td">Yes</td>
+<td class="td">Returns FALSE if the form element is not exactly the parameter value.</td>
+<td class="td">exact_length[8]</td>
+</tr><tr>
+
+<td class="td"><strong>alpha</strong></td>
+<td class="td">No</td>
+<td class="td">Returns FALSE if the form element contains anything other than alphabetical characters.</td>
+<td class="td"> </td>
+</tr><tr>
+
+<td class="td"><strong>alpha_numeric</strong></td>
+<td class="td">No</td>
+<td class="td">Returns FALSE if the form element contains anything other than alpha-numeric characters.</td>
+<td class="td"> </td>
+</tr><tr>
+
+<td class="td"><strong>alpha_dash</strong></td>
+<td class="td">No</td>
+<td class="td">Returns FALSE if the form element contains anything other than alpha-numeric characters, underscores or dashes.</td>
+<td class="td"> </td>
+</tr><tr>
+
+<td class="td"><strong>numeric</strong></td>
+<td class="td">No</td>
+<td class="td">Returns FALSE if the form element contains anything other than numeric characters.</td>
+<td class="td"> </td>
+</tr><tr>
+
+<td class="td"><strong>valid_email</strong></td>
+<td class="td">No</td>
+<td class="td">Returns FALSE if the form element does not contain a valid email address.</td>
+<td class="td"> </td>
+</tr>
+
+</table>
+
+<p><strong>Note:</strong> These rules can also be called as discreet functions. For example:</p>
+
+<code>$this->validation->required($string);</code>
+
+<p class="important"><strong>Note:</strong> You can also use any native PHP functions that permit one parameter.</p>
+
+
+
+<h2>Prepping Reference</h2>
+
+<p>The following is a list of all the prepping functions that are available to use:</p>
+
+
+
+<table cellpadding="0" cellspacing="1" border="0" style="width:100%" class="tableborder">
+<tr>
+<th>Name</th>
+<th>Parameter</th>
+<th>Description</th>
+</tr><tr>
+
+<td class="td"><strong>xss_clean</strong></td>
+<td class="td">No</td>
+<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"><strong>prep_for_form</strong></td>
+<td class="td">No</td>
+<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"><strong>prep_url</strong></td>
+<td class="td">No</td>
+<td class="td">Adds "http://" to URLs if missing.</td>
+</tr><tr>
+
+<td class="td"><strong>strip_image_tags</strong></td>
+<td class="td">No</td>
+<td class="td">Strips the HTML from image tags leaving the raw URL.</td>
+</tr><tr>
+
+<td class="td"><strong>encode_php_tags</strong></td>
+<td class="td">No</td>
+<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,
+like <kbd>trim</kbd>, <kbd>htmlspecialchars</kbd>, <kbd>urldecode</kbd>, etc.</p>
+
+
+<h2>Setting Custom Error Messages</h2>
+
+<p>All of the native error messages are located in the following language file: <dfn>language/english/validation_lang.php</dfn></p>
+
+<p>To set your own custom message you can either edit that file, or use the following function:</p>
+
+<code>$this->validation->set_message('<var>rule</var>', '<var>Error Message</var>');</code>
+
+<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>
+
+
+</div>
+<!-- END CONTENT -->
+
+
+<div id="footer">
+<p>
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+ ·
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+<p>
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