| <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> | |
| <html> | |
| <head> | |
| <title>Code Igniter User Guide</title> | |
| <style type='text/css' media='all'>@import url('../userguide.css');</style> | |
| <link rel='stylesheet' type='text/css' media='all' href='../userguide.css' /> | |
| <script type="text/javascript" src="../scripts/nav.js"></script> | |
| <script type="text/javascript" src="../scripts/prototype.lite.js"></script> | |
| <script type="text/javascript" src="../scripts/moo.fx.js"></script> | |
| <script type="text/javascript"> | |
| window.onload = function() { | |
| myHeight = new fx.Height('nav', {duration: 400}); | |
| myHeight.hide(); | |
| } | |
| </script> | |
| <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> | |
| <meta http-equiv='expires' content='-1' /> | |
| <meta http-equiv= 'pragma' content='no-cache' /> | |
| <meta name='robots' content='all' /> | |
| <meta name='author' content='Rick Ellis' /> | |
| <meta name='description' content='Code Igniter User Guide' /> | |
| </head> | |
| <body> | |
| <!-- START NAVIGATION --> | |
| <div id="nav"><div id="nav_inner"><script type="text/javascript">create_menu('../');</script></div></div> | |
| <div id="nav2"><a name="top"></a><a href="javascript:void(0);" onclick="myHeight.toggle();"><img src="../images/nav_toggle.jpg" width="153" height="44" border="0" title="Toggle Table of Contents" alt="Toggle Table of Contents" /></a></div> | |
| <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> | |
| <!-- END NAVIGATION --> | |
| <!-- START BREADCRUMB --> | |
| <table cellpadding="0" cellspacing="0" border="0" style="width:100%"> | |
| <tr> | |
| <td id="breadcrumb"> | |
| <a href="http://www.codeigniter.com/">Code Igniter Home</a> › | |
| <a href="../index.html">User Guide Home</a> › | |
| Models | |
| </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>Models</h1> | |
| <p>Models are <strong>optionally</strong> available for those who want to use a more | |
| traditional MVC approach.</p> | |
| <ul> | |
| <li><a href="#what">What is a Model?</a></li> | |
| <li><a href="#anatomy">Anatomy of a Model</a></li> | |
| <li><a href="#loading">Loading a Model</a></li> | |
| <li><a href="#conn">Connecting to your Database</a></li> | |
| </ul> | |
| <a name="what"></a> | |
| <h2>What is a Model?</h2> | |
| <p>Models are PHP classes that are designed to work with information in your database. For example, let's say | |
| you use Code Igniter to manage a blog. You might have a model class that contains functions to insert, update, and | |
| retrieve your blog data. Here is an example of what such a model class might look like:</p> | |
| <code> | |
| class Blogmodel extends Model {<br /> | |
| <br /> | |
| var $title = '';<br /> | |
| var $content = '';<br /> | |
| var $date = '';<br /> | |
| <br /> | |
| function Blogmodel()<br /> | |
| {<br /> | |
| // Call the Model constructor<br /> | |
| parent::Model();<br /> | |
| }<br /> | |
| <br /> | |
| function get_last_ten_entries()<br /> | |
| {<br /> | |
| $query = $this->db->get('entries', 10);<br /> | |
| return $query->result();<br /> | |
| }<br /> | |
| <br /> | |
| function insert_entry()<br /> | |
| {<br /> | |
| $this->title = $_POST['title'];<br /> | |
| $this->content = $_POST['content'];<br /> | |
| $this->date = time();<br /> | |
| <br /> | |
| $this->db->insert('entries', $this);<br /> | |
| }<br /> | |
| <br /> | |
| function update_entry()<br /> | |
| {<br /> | |
| $this->title = $_POST['title'];<br /> | |
| $this->content = $_POST['content'];<br /> | |
| $this->date = time();<br /> | |
| <br /> | |
| $this->db->update('entries', $this, array('id', $_POST['id']));<br /> | |
| }<br /> | |
| <br /> | |
| }</code> | |
| <p>Note: The functions in the above example use the <a href="../libraries/database/active_record.html">Active Record</a> database functions.</p> | |
| <a name="anatomy"></a> | |
| <h2>Anatomy of a Model</h2> | |
| <p>Model classes are stored in your <dfn>application/models/</dfn> folder. The basic prototype for a model is this:</p> | |
| <code> | |
| class <var>Model_name</var> extends Model {<br /> | |
| <br /> | |
| function <var>Model_name</var>()<br /> | |
| {<br /> | |
| parent::Model();<br /> | |
| }<br /> | |
| }</code> | |
| <p>Where <var>Model_name</var> is the name of your class. Class names <strong>must</strong> be capitalized. | |
| Make sure your class extends the base Model class.</p> | |
| <p>The file name will be a lower case version of your class name. For example, if your class is this:</p> | |
| <code> | |
| class <var>User_model</var> extends Model {<br /> | |
| <br /> | |
| function <var>User_model</var>()<br /> | |
| {<br /> | |
| parent::Model();<br /> | |
| }<br /> | |
| }</code> | |
| <p>Your file will be this:</p> | |
| <code>application/models/<var>user_model.php</var></code> | |
| <a name="loading"></a> | |
| <h2>Loading a Model</h2> | |
| <p>Your models will typically be loaded and called from within your <a href="controllers.html">controller</a> functions. | |
| To load a model you will use the following function:</p> | |
| <code>$this->load->model('<var>Model_name</var>');</code> | |
| <p>Once loaded, you will access your model functions using an object with the same name as your class:</p> | |
| <code> | |
| $this->load->model('<var>Model_name</var>');<br /> | |
| <br /> | |
| $this-><var>Model_name</var>->function(); | |
| </code> | |
| <p>If you would like your model assigned to a different object name you can specify it via the second parameter of the loading | |
| function:</p> | |
| <code> | |
| $this->load->model('<var>Model_name</var>', '<kbd>fubar</kbd>');<br /> | |
| <br /> | |
| $this-><kbd>fubar</kbd>->function(); | |
| </code> | |
| <p>Here is an example of a controller, that loads a model, then serves a view:</p> | |
| <code> | |
| class Blog_controller extends Controller {<br /> | |
| <br /> | |
| function blog()<br /> | |
| {<br /> | |
| $this->load->model('Blog');<br /> | |
| <br /> | |
| $data['query'] = $this->Blog->get_last_ten_entries();<br /><br /> | |
| $this->load->view('blog', $data);<br /> | |
| }<br /> | |
| }</code> | |
| <a name="conn"></a> | |
| <h2>Connecting to your Database</h2> | |
| <p>When a model is loaded it does <strong>NOT</strong> connect automatically to your database. The following options for connecting are available to you:</p> | |
| <ul> | |
| <li>You can connect using the standard database methods <a href="../libraries/database/connecting.html">described here</a>, either from within your Controller class or your Model class.</li> | |
| <li>You can tell the model loading function to auto-connect by passing <kbd>TRUE</kbd> (boolean) via the third parameter, | |
| and connectivity settings, as defined in your database config file will be used: | |
| <code>$this->load->model('<var>Model_name</var>', '', <kbd>TRUE</kbd>);</code> | |
| </li> | |
| <li>You can manually pass database connectivity settings via the third parameter: | |
| <code>$config['hostname'] = "localhost";<br /> | |
| $config['username'] = "myusername";<br /> | |
| $config['password'] = "mypassword";<br /> | |
| $config['database'] = "mydatabase";<br /> | |
| $config['dbdriver'] = "mysql";<br /> | |
| $config['dbprefix'] = "";<br /> | |
| $config['pconnect'] = FALSE;<br /> | |
| $config['db_debug'] = TRUE;<br /> | |
| $config['active_r'] = TRUE;<br /> | |
| <br /> | |
| $this->load->model('<var>Model_name</var>', '', <kbd>$config</kbd>);</code></li> | |
| </ul> | |
| </div> | |
| <!-- END CONTENT --> | |
| <div id="footer"> | |
| <p> | |
| Previous Topic: <a href="views.html">Views</a> | |
| · | |
| <a href="#top">Top of Page</a> · | |
| <a href="../index.html">User Guide Home</a> · | |
| Next Topic: <a href="helpers.html">Helpers</a> | |
| <p> | |
| <p><a href="http://www.codeigniter.com">Code Igniter</a> · Copyright © 2006 · <a href="http://www.pmachine.com">pMachine, Inc.</a></p> | |
| </div> | |
| </body> | |
| </html> |