diff options
| author | Derek Allard <derek.allard@ellislab.com> | 2008-11-13 23:59:24 +0100 |
|---|---|---|
| committer | Derek Allard <derek.allard@ellislab.com> | 2008-11-13 23:59:24 +0100 |
| commit | 2067d1a727e7eb5e5ffb40e967f3d1fc4c8a41b2 (patch) | |
| tree | a95e01024205837e9580757350d04b233e82503f /user_guide/general/controllers.html | |
| parent | dd9f932556d3cd45a1d06cc478f40d06b7649a69 (diff) | |
Changing EOL style to LF
Diffstat (limited to 'user_guide/general/controllers.html')
| -rw-r--r-- | user_guide/general/controllers.html | 768 |
1 files changed, 384 insertions, 384 deletions
diff --git a/user_guide/general/controllers.html b/user_guide/general/controllers.html index cb7f80eac..f11d09215 100644 --- a/user_guide/general/controllers.html +++ b/user_guide/general/controllers.html @@ -1,385 +1,385 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
-<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
-<head>
-
-<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
-<title>Controllers : CodeIgniter 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="../nav/nav.js"></script>
-<script type="text/javascript" src="../nav/prototype.lite.js"></script>
-<script type="text/javascript" src="../nav/moo.fx.js"></script>
-<script type="text/javascript" src="../nav/user_guide_menu.js"></script>
-
-<meta http-equiv='expires' content='-1' />
-<meta http-equiv= 'pragma' content='no-cache' />
-<meta name='robots' content='all' />
-<meta name='author' content='ExpressionEngine Dev Team' />
-<meta name='description' content='CodeIgniter 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_darker.jpg" width="154" height="43" 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>CodeIgniter User Guide Version 1.7</h1></td>
-<td id="breadcrumb_right"><a href="../toc.html">Table of Contents Page</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://codeigniter.com/">CodeIgniter Home</a> ›
-<a href="../index.html">User Guide Home</a> ›
-Controllers
-</td>
-<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="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>Controllers</h1>
-
-<p>Controllers are the heart of your application, as they determine how HTTP requests should be handled.</p>
-
-
-<ul>
-<li><a href="#what">What is a Controller?</a></li>
-<li><a href="#hello">Hello World</a></li>
-<li><a href="#functions">Functions</a></li>
-<li><a href="#passinguri">Passing URI Segments to Your Functions</a></li>
-<li><a href="#default">Defining a Default Controller</a></li>
-<li><a href="#remapping">Remapping Function Calls</a></li>
-<li><a href="#output">Controlling Output Data</a></li>
-<li><a href="#private">Private Functions</a></li>
-<li><a href="#subfolders">Organizing Controllers into Sub-folders</a></li>
-<li><a href="#constructors">Class Constructors</a></li>
-<li><a href="#reserved">Reserved Function Names</a></li>
-</ul>
-
-
-<a name="what"></a>
-<h2>What is a Controller?</h2>
-
-<p><dfn>A Controller is simply a class file that is named in a way that can be associated with a URI.</dfn></p>
-
-<p>Consider this URI:</p>
-
-<code>example.com/index.php/<var>blog</var>/</code>
-
-<p>In the above example, CodeIgniter would attempt to find a controller named <dfn>blog.php</dfn> and load it.</p>
-
-<p><strong>When a controller's name matches the first segment of a URI, it will be loaded.</strong></p>
-
-<a name="hello"></a>
-<h2>Let's try it: Hello World!</h2>
-
-<p>Let's create a simple controller so you can see it in action. Using your text editor, create a file called <dfn>blog.php</dfn>, and put the following code in it:</p>
-
-
-<textarea class="textarea" style="width:100%" cols="50" rows="10">
-<?php
-class Blog extends Controller {
-
- function index()
- {
- echo 'Hello World!';
- }
-}
-?>
-</textarea>
-
-
-
-<p>Then save the file to your <dfn>application/controllers/</dfn> folder.</p>
-
-<p>Now visit the your site using a URL similar to this:</p>
-
-<code>example.com/index.php/<var>blog</var>/</code>
-
-<p>If you did it right, you should see <samp>Hello World!</samp>.</p>
-
-<p>Note: Class names must start with an uppercase letter. In other words, this is valid:</p>
-
-<code><?php<br />
-class <var>Blog</var> extends Controller {<br />
-<br />
-}<br />
-?></code>
-
-<p>This is <strong>not</strong> valid:</p>
-
-<code><?php<br />
-class <var>blog</var> extends Controller {<br />
-<br />
-}<br />
-?></code>
-
-<p>Also, always make sure your controller <dfn>extends</dfn> the parent controller class so that it can inherit all its functions.</p>
-
-
-
-<a name="functions"></a>
-<h2>Functions</h2>
-
-<p>In the above example the function name is <dfn>index()</dfn>. The "index" function is always loaded by default if the
-<strong>second segment</strong> of the URI is empty. Another way to show your "Hello World" message would be this:</p>
-
-<code>example.com/index.php/<var>blog</var>/<samp>index</samp>/</code>
-
-<p><strong>The second segment of the URI determines which function in the controller gets called.</strong></p>
-
-<p>Let's try it. Add a new function to your controller:</p>
-
-
-<textarea class="textarea" style="width:100%" cols="50" rows="15">
-<?php
-class Blog extends Controller {
-
- function index()
- {
- echo 'Hello World!';
- }
-
- function comments()
- {
- echo 'Look at this!';
- }
-}
-?>
-</textarea>
-
-<p>Now load the following URL to see the <dfn>comment</dfn> function:</p>
-
-<code>example.com/index.php/<var>blog</var>/<samp>comments</samp>/</code>
-
-<p>You should see your new message.</p>
-
-<a name="passinguri"></a>
-<h2>Passing URI Segments to your Functions</h2>
-
-<p>If your URI contains more then two segments they will be passed to your function as parameters.</p>
-
-<p>For example, lets say you have a URI like this:</p>
-
-<code>example.com/index.php/<var>products</var>/<samp>shoes</samp>/<kbd>sandals</kbd>/<dfn>123</dfn></code>
-
-<p>Your function will be passed URI segments 3 and 4 ("sandals" and "123"):</p>
-
-<code>
-<?php<br />
-class Products extends Controller {<br />
-<br />
- function shoes($sandals, $id)<br />
- {<br />
- echo $sandals;<br />
- echo $id;<br />
- }<br />
-}<br />
-?>
-</code>
-
-<p class="important"><strong>Important:</strong> If you are using the <a href="routing.html">URI Routing</a> feature, the segments
-passed to your function will be the re-routed ones.</p>
-
-
-<a name="default"></a>
-<h2>Defining a Default Controller</h2>
-
-<p>CodeIgniter can be told to load a default controller when a URI is not present,
-as will be the case when only your site root URL is requested. To specify a default controller, open
-your <dfn>application/config/routes.php</dfn> file and set this variable:</p>
-
-<code>$route['default_controller'] = '<var>Blog</var>';</code>
-
-<p>Where <var>Blog</var> is the name of the controller class you want used. If you now load your main index.php file without
-specifying any URI segments you'll see your Hello World message by default.</p>
-
-
-
-<a name="remapping"></a>
-<h2>Remapping Function Calls</h2>
-
-<p>As noted above, the second segment of the URI typically determines which function in the controller gets called.
-CodeIgniter permits you to override this behavior through the use of the <kbd>_remap()</kbd> function:</p>
-
-<code>function _remap()<br />
-{<br />
- // Some code here...<br />
-}</code>
-
-<p class="important"><strong>Important:</strong> If your controller contains a function named <kbd>_remap()</kbd>, it will <strong>always</strong>
-get called regardless of what your URI contains. It overrides the normal behavior in which the URI determines which function is called,
-allowing you to define your own function routing rules.</p>
-
-<p>The overridden function call (typically the second segment of the URI) will be passed as a parameter the <kbd>_remap()</kbd> function:</p>
-
-<code>function _remap(<var>$method</var>)<br />
-{<br />
- if ($method == 'some_method')<br />
- {<br />
- $this->$method();<br />
- }<br />
- else<br />
- {<br />
- $this->default_method();<br />
- }<br />
-}</code>
-
-
-
-
-
-<a name="output"></a>
-<h2>Processing Output</h2>
-
-<p>CodeIgniter has an output class that takes care of sending your final rendered data to the web browser automatically. More information on this can be found in the
-<a href="views.html">Views</a> and <a href="../libraries/output.html">Output class</a> pages. In some cases, however, you might want to
-post-process the finalized data in some way and send it to the browser yourself. CodeIgniter permits you to
-add a function named <dfn>_output()</dfn> to your controller that will receive the finalized output data.</p>
-
-<p><strong>Important:</strong> If your controller contains a function named <kbd>_output()</kbd>, it will <strong>always</strong>
-be called by the output class instead of echoing the finalized data directly. The first parameter of the function will contain the finalized output.</p>
-
-<p>Here is an example:</p>
-
-<code>
-function _output($output)<br />
-{<br />
- echo $output;<br />
-}</code>
-
-<p class="important">Please note that your <dfn>_output()</dfn> function will receive the data in its finalized state. Benchmark and memory usage data will be rendered,
-cache files written (if you have caching enabled), and headers will be sent (if you use that <a href="../libraries/output.html">feature</a>)
-before it is handed off to the _output() function. If you are using this feature the page execution timer and memory usage stats might not be perfectly accurate
-since they will not take into acccount any further processing you do. For an alternate way to control output <em>before</em> any of the final processing is done, please see
-the available methods in the <a href="../libraries/output.html">Output Class</a>.</p>
-
-<a name="private"></a>
-<h2>Private Functions</h2>
-
-
-<p>In some cases you may want certain functions hidden from public access. To make a function private, simply add an
-underscore as the name prefix and it will not be served via a URL request. For example, if you were to have a function like this:</p>
-
-<code>
-function _utility()<br />
-{<br />
- // some code<br />
-}</code>
-
-<p>Trying to access it via the URL, like this, will not work:</p>
-
-<code>example.com/index.php/<var>blog</var>/<samp>_utility</samp>/</code>
-
-
-
-<a name="subfolders"></a>
-<h2>Organizing Your Controllers into Sub-folders</h2>
-
-<p>If you are building a large application you might find it convenient to organize your controllers into sub-folders. CodeIgniter permits you to do this.</p>
-
-<p>Simply create folders within your <dfn>application/controllers</dfn> directory and place your controller classes within them.</p>
-
-<p><strong>Note:</strong> When using this feature the first segment of your URI must specify the folder. For example, lets say you have a controller
-located here:</p>
-
-<code>application/controllers/<kbd>products</kbd>/shoes.php</code>
-
-<p>To call the above controller your URI will look something like this:</p>
-
-<code>example.com/index.php/products/shoes/show/123</code>
-
-<p>Each of your sub-folders may contain a default controller which will be
-called if the URL contains only the sub-folder. Simply name your default controller as specified in your
-<dfn>application/config/routes.php</dfn> file</p>
-
-
-<p>CodeIgniter also permits you to remap your URIs using its <a href="routing.html">URI Routing</a> feature.</p>
-
-
-<h2><a name="constructors"></a>Class Constructors</h2>
-
-
-<p>If you intend to use a constructor in any of your Controllers, you <strong>MUST</strong> place the following line of code in it:</p>
-
-<code>parent::Controller();</code>
-
-<p>The reason this line is necessary is because your local constructor will be overriding the one in the parent controller class so we need to manually call it.</p>
-
-
-<p>If you are not familiar with constructors, in PHP 4, a <em>constructor</em> is simply a function that has the exact same name as the class:</p>
-
-<code>
-<?php<br />
-class <kbd>Blog</kbd> extends Controller {<br />
-<br />
- function <kbd>Blog()</kbd><br />
- {<br />
- <var>parent::Controller();</var><br />
- }<br />
-}<br />
-?></code>
-
-<p>In PHP 5, constructors use the following syntax:</p>
-
-<code>
-<?php<br />
-class <kbd>Blog</kbd> extends Controller {<br />
-<br />
- function <kbd>__construct()</kbd><br />
- {<br />
- <var>parent::Controller();</var><br />
- }<br />
-}<br />
-?></code>
-
-<p>Constructors are useful if you need to set some default values, or run a default process when your class is instantiated.
-Constructors can't return a value, but they can do some default work.</p>
-
-<a name="reserved"></a>
-<h2>Reserved Function Names</h2>
-
-<p>Since your controller classes will extend the main application controller you
-must be careful not to name your functions identically to the ones used by that class, otherwise your local functions
-will override them. See <a href="reserved_names.html">Reserved Names</a> for a full list.</p>
-
-<h2>That's it!</h2>
-
-<p>That, in a nutshell, is all there is to know about controllers.</p>
-
-
-
-</div>
-<!-- END CONTENT -->
-
-
-<div id="footer">
-<p>
-Previous Topic: <a href="urls.html">CodeIgniter URLs</a>
- ·
-<a href="#top">Top of Page</a> ·
-<a href="../index.html">User Guide Home</a> ·
-Next Topic: <a href="reserved_names.html">Reserved Names</a></p>
-<p><a href="http://codeigniter.com">CodeIgniter</a> · Copyright © 2006-2008 · <a href="http://ellislab.com/">Ellislab, Inc.</a></p>
-</div>
-
-</body>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> +<head> + +<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> +<title>Controllers : CodeIgniter 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="../nav/nav.js"></script> +<script type="text/javascript" src="../nav/prototype.lite.js"></script> +<script type="text/javascript" src="../nav/moo.fx.js"></script> +<script type="text/javascript" src="../nav/user_guide_menu.js"></script> + +<meta http-equiv='expires' content='-1' /> +<meta http-equiv= 'pragma' content='no-cache' /> +<meta name='robots' content='all' /> +<meta name='author' content='ExpressionEngine Dev Team' /> +<meta name='description' content='CodeIgniter 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_darker.jpg" width="154" height="43" 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>CodeIgniter User Guide Version 1.7</h1></td> +<td id="breadcrumb_right"><a href="../toc.html">Table of Contents Page</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://codeigniter.com/">CodeIgniter Home</a> › +<a href="../index.html">User Guide Home</a> › +Controllers +</td> +<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="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>Controllers</h1> + +<p>Controllers are the heart of your application, as they determine how HTTP requests should be handled.</p> + + +<ul> +<li><a href="#what">What is a Controller?</a></li> +<li><a href="#hello">Hello World</a></li> +<li><a href="#functions">Functions</a></li> +<li><a href="#passinguri">Passing URI Segments to Your Functions</a></li> +<li><a href="#default">Defining a Default Controller</a></li> +<li><a href="#remapping">Remapping Function Calls</a></li> +<li><a href="#output">Controlling Output Data</a></li> +<li><a href="#private">Private Functions</a></li> +<li><a href="#subfolders">Organizing Controllers into Sub-folders</a></li> +<li><a href="#constructors">Class Constructors</a></li> +<li><a href="#reserved">Reserved Function Names</a></li> +</ul> + + +<a name="what"></a> +<h2>What is a Controller?</h2> + +<p><dfn>A Controller is simply a class file that is named in a way that can be associated with a URI.</dfn></p> + +<p>Consider this URI:</p> + +<code>example.com/index.php/<var>blog</var>/</code> + +<p>In the above example, CodeIgniter would attempt to find a controller named <dfn>blog.php</dfn> and load it.</p> + +<p><strong>When a controller's name matches the first segment of a URI, it will be loaded.</strong></p> + +<a name="hello"></a> +<h2>Let's try it: Hello World!</h2> + +<p>Let's create a simple controller so you can see it in action. Using your text editor, create a file called <dfn>blog.php</dfn>, and put the following code in it:</p> + + +<textarea class="textarea" style="width:100%" cols="50" rows="10"> +<?php +class Blog extends Controller { + + function index() + { + echo 'Hello World!'; + } +} +?> +</textarea> + + + +<p>Then save the file to your <dfn>application/controllers/</dfn> folder.</p> + +<p>Now visit the your site using a URL similar to this:</p> + +<code>example.com/index.php/<var>blog</var>/</code> + +<p>If you did it right, you should see <samp>Hello World!</samp>.</p> + +<p>Note: Class names must start with an uppercase letter. In other words, this is valid:</p> + +<code><?php<br /> +class <var>Blog</var> extends Controller {<br /> +<br /> +}<br /> +?></code> + +<p>This is <strong>not</strong> valid:</p> + +<code><?php<br /> +class <var>blog</var> extends Controller {<br /> +<br /> +}<br /> +?></code> + +<p>Also, always make sure your controller <dfn>extends</dfn> the parent controller class so that it can inherit all its functions.</p> + + + +<a name="functions"></a> +<h2>Functions</h2> + +<p>In the above example the function name is <dfn>index()</dfn>. The "index" function is always loaded by default if the +<strong>second segment</strong> of the URI is empty. Another way to show your "Hello World" message would be this:</p> + +<code>example.com/index.php/<var>blog</var>/<samp>index</samp>/</code> + +<p><strong>The second segment of the URI determines which function in the controller gets called.</strong></p> + +<p>Let's try it. Add a new function to your controller:</p> + + +<textarea class="textarea" style="width:100%" cols="50" rows="15"> +<?php +class Blog extends Controller { + + function index() + { + echo 'Hello World!'; + } + + function comments() + { + echo 'Look at this!'; + } +} +?> +</textarea> + +<p>Now load the following URL to see the <dfn>comment</dfn> function:</p> + +<code>example.com/index.php/<var>blog</var>/<samp>comments</samp>/</code> + +<p>You should see your new message.</p> + +<a name="passinguri"></a> +<h2>Passing URI Segments to your Functions</h2> + +<p>If your URI contains more then two segments they will be passed to your function as parameters.</p> + +<p>For example, lets say you have a URI like this:</p> + +<code>example.com/index.php/<var>products</var>/<samp>shoes</samp>/<kbd>sandals</kbd>/<dfn>123</dfn></code> + +<p>Your function will be passed URI segments 3 and 4 ("sandals" and "123"):</p> + +<code> +<?php<br /> +class Products extends Controller {<br /> +<br /> + function shoes($sandals, $id)<br /> + {<br /> + echo $sandals;<br /> + echo $id;<br /> + }<br /> +}<br /> +?> +</code> + +<p class="important"><strong>Important:</strong> If you are using the <a href="routing.html">URI Routing</a> feature, the segments +passed to your function will be the re-routed ones.</p> + + +<a name="default"></a> +<h2>Defining a Default Controller</h2> + +<p>CodeIgniter can be told to load a default controller when a URI is not present, +as will be the case when only your site root URL is requested. To specify a default controller, open +your <dfn>application/config/routes.php</dfn> file and set this variable:</p> + +<code>$route['default_controller'] = '<var>Blog</var>';</code> + +<p>Where <var>Blog</var> is the name of the controller class you want used. If you now load your main index.php file without +specifying any URI segments you'll see your Hello World message by default.</p> + + + +<a name="remapping"></a> +<h2>Remapping Function Calls</h2> + +<p>As noted above, the second segment of the URI typically determines which function in the controller gets called. +CodeIgniter permits you to override this behavior through the use of the <kbd>_remap()</kbd> function:</p> + +<code>function _remap()<br /> +{<br /> + // Some code here...<br /> +}</code> + +<p class="important"><strong>Important:</strong> If your controller contains a function named <kbd>_remap()</kbd>, it will <strong>always</strong> +get called regardless of what your URI contains. It overrides the normal behavior in which the URI determines which function is called, +allowing you to define your own function routing rules.</p> + +<p>The overridden function call (typically the second segment of the URI) will be passed as a parameter the <kbd>_remap()</kbd> function:</p> + +<code>function _remap(<var>$method</var>)<br /> +{<br /> + if ($method == 'some_method')<br /> + {<br /> + $this->$method();<br /> + }<br /> + else<br /> + {<br /> + $this->default_method();<br /> + }<br /> +}</code> + + + + + +<a name="output"></a> +<h2>Processing Output</h2> + +<p>CodeIgniter has an output class that takes care of sending your final rendered data to the web browser automatically. More information on this can be found in the +<a href="views.html">Views</a> and <a href="../libraries/output.html">Output class</a> pages. In some cases, however, you might want to +post-process the finalized data in some way and send it to the browser yourself. CodeIgniter permits you to +add a function named <dfn>_output()</dfn> to your controller that will receive the finalized output data.</p> + +<p><strong>Important:</strong> If your controller contains a function named <kbd>_output()</kbd>, it will <strong>always</strong> +be called by the output class instead of echoing the finalized data directly. The first parameter of the function will contain the finalized output.</p> + +<p>Here is an example:</p> + +<code> +function _output($output)<br /> +{<br /> + echo $output;<br /> +}</code> + +<p class="important">Please note that your <dfn>_output()</dfn> function will receive the data in its finalized state. Benchmark and memory usage data will be rendered, +cache files written (if you have caching enabled), and headers will be sent (if you use that <a href="../libraries/output.html">feature</a>) +before it is handed off to the _output() function. If you are using this feature the page execution timer and memory usage stats might not be perfectly accurate +since they will not take into acccount any further processing you do. For an alternate way to control output <em>before</em> any of the final processing is done, please see +the available methods in the <a href="../libraries/output.html">Output Class</a>.</p> + +<a name="private"></a> +<h2>Private Functions</h2> + + +<p>In some cases you may want certain functions hidden from public access. To make a function private, simply add an +underscore as the name prefix and it will not be served via a URL request. For example, if you were to have a function like this:</p> + +<code> +function _utility()<br /> +{<br /> + // some code<br /> +}</code> + +<p>Trying to access it via the URL, like this, will not work:</p> + +<code>example.com/index.php/<var>blog</var>/<samp>_utility</samp>/</code> + + + +<a name="subfolders"></a> +<h2>Organizing Your Controllers into Sub-folders</h2> + +<p>If you are building a large application you might find it convenient to organize your controllers into sub-folders. CodeIgniter permits you to do this.</p> + +<p>Simply create folders within your <dfn>application/controllers</dfn> directory and place your controller classes within them.</p> + +<p><strong>Note:</strong> When using this feature the first segment of your URI must specify the folder. For example, lets say you have a controller +located here:</p> + +<code>application/controllers/<kbd>products</kbd>/shoes.php</code> + +<p>To call the above controller your URI will look something like this:</p> + +<code>example.com/index.php/products/shoes/show/123</code> + +<p>Each of your sub-folders may contain a default controller which will be +called if the URL contains only the sub-folder. Simply name your default controller as specified in your +<dfn>application/config/routes.php</dfn> file</p> + + +<p>CodeIgniter also permits you to remap your URIs using its <a href="routing.html">URI Routing</a> feature.</p> + + +<h2><a name="constructors"></a>Class Constructors</h2> + + +<p>If you intend to use a constructor in any of your Controllers, you <strong>MUST</strong> place the following line of code in it:</p> + +<code>parent::Controller();</code> + +<p>The reason this line is necessary is because your local constructor will be overriding the one in the parent controller class so we need to manually call it.</p> + + +<p>If you are not familiar with constructors, in PHP 4, a <em>constructor</em> is simply a function that has the exact same name as the class:</p> + +<code> +<?php<br /> +class <kbd>Blog</kbd> extends Controller {<br /> +<br /> + function <kbd>Blog()</kbd><br /> + {<br /> + <var>parent::Controller();</var><br /> + }<br /> +}<br /> +?></code> + +<p>In PHP 5, constructors use the following syntax:</p> + +<code> +<?php<br /> +class <kbd>Blog</kbd> extends Controller {<br /> +<br /> + function <kbd>__construct()</kbd><br /> + {<br /> + <var>parent::Controller();</var><br /> + }<br /> +}<br /> +?></code> + +<p>Constructors are useful if you need to set some default values, or run a default process when your class is instantiated. +Constructors can't return a value, but they can do some default work.</p> + +<a name="reserved"></a> +<h2>Reserved Function Names</h2> + +<p>Since your controller classes will extend the main application controller you +must be careful not to name your functions identically to the ones used by that class, otherwise your local functions +will override them. See <a href="reserved_names.html">Reserved Names</a> for a full list.</p> + +<h2>That's it!</h2> + +<p>That, in a nutshell, is all there is to know about controllers.</p> + + + +</div> +<!-- END CONTENT --> + + +<div id="footer"> +<p> +Previous Topic: <a href="urls.html">CodeIgniter URLs</a> + · +<a href="#top">Top of Page</a> · +<a href="../index.html">User Guide Home</a> · +Next Topic: <a href="reserved_names.html">Reserved Names</a></p> +<p><a href="http://codeigniter.com">CodeIgniter</a> · Copyright © 2006-2008 · <a href="http://ellislab.com/">Ellislab, Inc.</a></p> +</div> + +</body> </html>
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