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diff --git a/user_guide/libraries/input.html b/user_guide/libraries/input.html new file mode 100644 index 000000000..0878f9d1e --- /dev/null +++ b/user_guide/libraries/input.html @@ -0,0 +1,207 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html>
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+
+<title>Code Igniter User Guide</title>
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+<style type='text/css' media='all'>@import url('../userguide.css');</style>
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+<script type="text/javascript" src="../scripts/moo.fx.js"></script>
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+ myHeight.hide();
+}
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+<meta name='author' content='Rick Ellis' />
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+<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 -->
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+<!-- 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> ›
+Input and Security Class
+</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>
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+
+<br clear="all" />
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+<!-- START CONTENT -->
+<div id="content">
+
+
+<h1>Input Class</h1>
+
+<p>The Input Class serves two purposes:</p>
+
+<ol>
+<li>It pre-processes global input data for security.</li>
+<li>It provides some helper functions for fetching input data and pre-processing it.</li>
+</ol>
+
+<p class="important"><strong>Note:</strong> This class is initialized automatically by the system so there is no need to do it manually.</p>
+
+
+<h2>Security Filtering</h2>
+
+<p>The security filtering function is called automatically when a new <a href="../general/controllers.html">controller</a> is invoked. It does the following:</p>
+
+<ul>
+<li>Destroys the global GET array. Since Code Igniter does not utilize GET strings, there is no reason to allow it.</li>
+<li>Destroys all global variables in the event register_globals is turned on.</li>
+<li>Filters the POST/COOKIE array keys, permitting only alpha-numeric (and a few other) characters.</li>
+<li>Provides XSS (Cross-site Scripting Hacks) filtering. This can be enabled globally, or upon request.</li>
+<li>Standardizes newline characters to \n</li>
+</ul>
+
+
+<h2>XSS Filtering</h2>
+
+<p>Code Igniter comes with a Cross Site Scripting Hack prevention filter which can either run automatically to filter
+all POST and COOKIE data that is encountered, or you can run it on a per item basis. By default it does <strong>not</strong>
+run globally since it requires a bit of processing overhead, and since you may not need it in all cases.</p>
+
+<p>The XSS filter looks for commonly used techniques to trigger Javascript or other types of code that attempt to hijack cookies
+or do other malicious things. If anything disallowed is encountered it is rendered safe by converting the data to character entities.</p>
+
+<p>
+Note: This function should only be used to deal with data upon submission. It's not something that should be used for general runtime processing since it requires a fair amount of processing overhead.</p>
+
+
+<p>To filter data through the XSS filter use this function:</p>
+
+<h2>$this->input->xss_clean()</h2>
+
+<p>Here is an usage example:</p>
+
+<code>$data = $this->input->xss_clean($data);</code>
+
+<p>If you want the filter to run automatically every time it encounters POST or COOKIE data you can enable it by opening your
+<kbd>application/config/config.php</kbd> file and setting this:
+
+<code>$config['global_xss_filtering'] = TRUE;</code>
+
+<p>Note: If you use the form validation class, it gives you the option of XSS filtering as well.</p>
+
+
+
+
+<h2>Using POST or COOKIE Data</h2>
+
+<p>Code Igniter comes with two helper functions that let you fetch POST or COOKIE items. The main advantage of using the provided
+functions rather then fetching an item directly ($_POST['something']) is that the functions will check to see if the item is set and
+return false (boolean) if not. This lets you conveniently use data without having to test whether an item exists first.
+In other words, normally you might do something like this:
+
+<code>
+if ( ! isset($_POST['something']))<br />
+{<br />
+ $something = FALSE;<br />
+}<br />
+else<br />
+{<br />
+ $something = $_POST['something'];<br />
+}</code>
+
+<p>With Code Igniter's built in functions you can simply do this:</p>
+
+<code>$something = $this->input->post('something');</code>
+
+<p>The two functions are:</p>
+
+<h2>$this->input->post()</h2>
+
+<p>The first parameter will contain the name of the POST item you are looking for:</p>
+
+<code>$this->input->post('some_data');</code>
+
+<p>The function returns FALSE (boolean) if the item you are attempting to retrieve does not exist.</p>
+
+<p>The second optional parameter lets you run the data through the XSS filter. It's enabled by setting the second parameter to boolean TRUE;</p>
+
+<code>$this->input->post('some_data', TRUE);</code>
+
+<h2>$this->input->cookie()</h2>
+
+<p>This function is identical to the post function, only it fetches cookie data:</p>
+
+<code>$this->input->cookie('some_data', TRUE);</code>
+
+
+
+
+<h2>$this->input->ip_address()</h2>
+<p>Returns the IP address for the current user. If the IP address is not valid, the function will return an IP of: 0.0.0.0</p>
+<code>echo $this->input->ip_address();</code>
+
+
+<h2>$this->input->valid_ip(<var>$ip</var>)</h2>
+
+<p>Takes an IP address as input and returns TRUE or FALSE (boolean) if it is valid or not. Note: The $this->input->ip_address() function above
+validates the IP automatically.</p>
+
+<code>if ( ! valid_id($ip))<br />
+{<br />
+ echo 'Not Valid';<br />
+}<br />
+else<br />
+{<br />
+ echo 'Valid';<br />
+}</code>
+
+
+<h2>$this->input->user_agent()</h2>
+<p>Returns the user agent (web browser) being used by the current user. Returns FALSE if it's not available.</p>
+<code>echo $this->input->user_agent();</code>
+
+
+
+
+</div>
+<!-- END CONTENT -->
+
+
+<div id="footer">
+<p>
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+ ·
+<a href="#top">Top of Page</a> ·
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+
+</body>
+</html>
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