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class="toctree-l2"><a class="reference internal" href="../helpers/number_helper.html">Number Helper</a></li> <li class="toctree-l2"><a class="reference internal" href="../helpers/path_helper.html">Path Helper</a></li> <li class="toctree-l2"><a class="reference internal" href="../helpers/security_helper.html">Security Helper</a></li> <li class="toctree-l2"><a class="reference internal" href="../helpers/smiley_helper.html">Smiley Helper</a></li> <li class="toctree-l2"><a class="reference internal" href="../helpers/string_helper.html">String Helper</a></li> <li class="toctree-l2"><a class="reference internal" href="../helpers/text_helper.html">Text Helper</a></li> <li class="toctree-l2"><a class="reference internal" href="../helpers/typography_helper.html">Typography Helper</a></li> <li class="toctree-l2"><a class="reference internal" href="../helpers/url_helper.html">URL Helper</a></li> <li class="toctree-l2"><a class="reference internal" href="../helpers/xml_helper.html">XML Helper</a></li> </ul> </li> </ul> </div> </nav> <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap"> <nav class="wy-nav-top" role="navigation" aria-label="top navigation"> <i data-toggle="wy-nav-top" class="fa fa-bars"></i> <a href="../index.html">CodeIgniter</a> </nav> <div class="wy-nav-content"> <div class="rst-content"> <div role="navigation" aria-label="breadcrumbs navigation"> <ul class="wy-breadcrumbs"> <li><a href="../index.html">Docs</a> »</li> <li><a href="index.html">General Topics</a> »</li> <li>Web Page Caching</li> <li class="wy-breadcrumbs-aside"> </li> <div style="float:right;margin-left:5px;" id="closeMe"> <img title="Classic Layout" alt="classic layout" src="data:image/gif;base64,R0lGODlhFAAUAJEAAAAAADMzM////wAAACH5BAUUAAIALAAAAAAUABQAAAImlI+py+0PU5gRBRDM3DxbWoXis42X13USOLauUIqnlsaH/eY6UwAAOw==" /> </div> </ul> <hr/> </div> <div role="main" class="document"> <div class="section" id="web-page-caching"> <h1>Web Page Caching<a class="headerlink" href="#web-page-caching" title="Permalink to this headline">¶</a></h1> <p>CodeIgniter lets you cache your pages in order to achieve maximum performance.</p> <p>Although CodeIgniter is quite fast, the amount of dynamic information you display in your pages will correlate directly to the server resources, memory, and processing cycles utilized, which affect your page load speeds. By caching your pages, since they are saved in their fully rendered state, you can achieve performance that nears that of static web pages.</p> <div class="section" id="how-does-caching-work"> <h2>How Does Caching Work?<a class="headerlink" href="#how-does-caching-work" title="Permalink to this headline">¶</a></h2> <p>Caching can be enabled on a per-page basis, and you can set the length of time that a page should remain cached before being refreshed. When a page is loaded for the first time, the cache file will be written to your application/cache folder. On subsequent page loads the cache file will be retrieved and sent to the requesting user’s browser. If it has expired, it will be deleted and refreshed before being sent to the browser.</p> </div> <div class="section" id="enabling-caching"> <h2>Enabling Caching<a class="headerlink" href="#enabling-caching" title="Permalink to this headline">¶</a></h2> <p>To enable caching, put the following tag in any of your controller methods:</p> <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-></span><span class="na">output</span><span class="o">-></span><span class="na">cache</span><span class="p">(</span><span class="nv">$n</span><span class="p">);</span> </pre></div> </div> <p>Where <code class="docutils literal"><span class="pre">$n</span></code> is the number of <strong>minutes</strong> you wish the page to remain cached between refreshes.</p> <p>The above tag can go anywhere within a method. It is not affected by the order that it appears, so place it wherever it seems most logical to you. Once the tag is in place, your pages will begin being cached.</p> <div class="admonition important"> <p class="first admonition-title">Important</p> <p class="last">Because of the way CodeIgniter stores content for output, caching will only work if you are generating display for your controller with a <a class="reference internal" href="views.html"><span class="doc">view</span></a>.</p> </div> <div class="admonition important"> <p class="first admonition-title">Important</p> <p class="last">If you change configuration options that might affect your output, you have to manually delete your cache files.</p> </div> <div class="admonition note"> <p class="first admonition-title">Note</p> <p class="last">Before the cache files can be written you must set the file permissions on your <em>application/cache/</em> directory such that it is writable.</p> </div> </div> <div class="section" id="deleting-caches"> <h2>Deleting Caches<a class="headerlink" href="#deleting-caches" title="Permalink to this headline">¶</a></h2> <p>If you no longer wish to cache a file you can remove the caching tag and it will no longer be refreshed when it expires.</p> <div class="admonition note"> <p class="first admonition-title">Note</p> <p class="last">Removing the tag will not delete the cache immediately. It will have to expire normally.</p> </div> <p>If you need to manually delete the cache, you can use the <code class="docutils literal"><span class="pre">delete_cache()</span></code> method:</p> <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="c1">// Deletes cache for the currently requested URI</span> <span class="nv">$this</span><span class="o">-></span><span class="na">output</span><span class="o">-></span><span class="na">delete_cache</span><span class="p">();</span> <span class="c1">// Deletes cache for /foo/bar</span> <span class="nv">$this</span><span class="o">-></span><span class="na">output</span><span class="o">-></span><span class="na">delete_cache</span><span class="p">(</span><span class="s1">'/foo/bar'</span><span class="p">);</span> </pre></div> </div> </div> </div> </div> <footer> <div class="rst-footer-buttons" role="navigation" aria-label="footer navigation"> <a href="profiling.html" class="btn btn-neutral float-right" title="Profiling Your Application">Next <span class="fa fa-arrow-circle-right"></span></a> <a href="errors.html" class="btn btn-neutral" title="Error Handling"><span class="fa fa-arrow-circle-left"></span> Previous</a> </div> <hr/> <div role="contentinfo"> <p> © Copyright 2014 - 2019, British Columbia Institute of Technology. Last updated on Sep 19, 2019. </p> </div> Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/snide/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>. </footer> </div> </div> </section> </div> <script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT:'../', VERSION:'3.1.11', COLLAPSE_INDEX:false, FILE_SUFFIX:'.html', HAS_SOURCE: false }; </script> <script type="text/javascript" src="../_static/jquery.js"></script> <script type="text/javascript" src="../_static/underscore.js"></script> <script type="text/javascript" src="../_static/doctools.js"></script> <script type="text/javascript" src="../_static/js/theme.js"></script> <script type="text/javascript"> jQuery(function () { SphinxRtdTheme.StickyNav.enable(); }); </script> </body> </html> Save