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  1. <!DOCTYPE html>
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  7. <title>Creating Libraries &mdash; CodeIgniter 3.1.11 documentation</title>
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  64. <li class="toctree-l1 current"><a class="reference internal" href="index.html">General Topics</a><ul class="current">
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  69. <li class="toctree-l2"><a class="reference internal" href="models.html">Models</a></li>
  70. <li class="toctree-l2"><a class="reference internal" href="helpers.html">Helpers</a></li>
  71. <li class="toctree-l2"><a class="reference internal" href="libraries.html">Using CodeIgniter Libraries</a></li>
  72. <li class="toctree-l2 current"><a class="current reference internal" href="#">Creating Libraries</a></li>
  73. <li class="toctree-l2"><a class="reference internal" href="drivers.html">Using CodeIgniter Drivers</a></li>
  74. <li class="toctree-l2"><a class="reference internal" href="creating_drivers.html">Creating Drivers</a></li>
  75. <li class="toctree-l2"><a class="reference internal" href="core_classes.html">Creating Core System Classes</a></li>
  76. <li class="toctree-l2"><a class="reference internal" href="ancillary_classes.html">Creating Ancillary Classes</a></li>
  77. <li class="toctree-l2"><a class="reference internal" href="hooks.html">Hooks - Extending the Framework Core</a></li>
  78. <li class="toctree-l2"><a class="reference internal" href="autoloader.html">Auto-loading Resources</a></li>
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  82. <li class="toctree-l2"><a class="reference internal" href="errors.html">Error Handling</a></li>
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  87. <li class="toctree-l2"><a class="reference internal" href="environments.html">Handling Multiple Environments</a></li>
  88. <li class="toctree-l2"><a class="reference internal" href="alternative_php.html">Alternate PHP Syntax for View Files</a></li>
  89. <li class="toctree-l2"><a class="reference internal" href="security.html">Security</a></li>
  90. <li class="toctree-l2"><a class="reference internal" href="styleguide.html">PHP Style Guide</a></li>
  91. </ul>
  92. </li>
  93. </ul>
  94. <ul>
  95. <li class="toctree-l1"><a class="reference internal" href="../libraries/index.html">Libraries</a><ul>
  96. <li class="toctree-l2"><a class="reference internal" href="../libraries/benchmark.html">Benchmarking Class</a></li>
  97. <li class="toctree-l2"><a class="reference internal" href="../libraries/caching.html">Caching Driver</a></li>
  98. <li class="toctree-l2"><a class="reference internal" href="../libraries/calendar.html">Calendaring Class</a></li>
  99. <li class="toctree-l2"><a class="reference internal" href="../libraries/cart.html">Shopping Cart Class</a></li>
  100. <li class="toctree-l2"><a class="reference internal" href="../libraries/config.html">Config Class</a></li>
  101. <li class="toctree-l2"><a class="reference internal" href="../libraries/email.html">Email Class</a></li>
  102. <li class="toctree-l2"><a class="reference internal" href="../libraries/encrypt.html">Encrypt Class</a></li>
  103. <li class="toctree-l2"><a class="reference internal" href="../libraries/encryption.html">Encryption Library</a></li>
  104. <li class="toctree-l2"><a class="reference internal" href="../libraries/file_uploading.html">File Uploading Class</a></li>
  105. <li class="toctree-l2"><a class="reference internal" href="../libraries/form_validation.html">Form Validation</a></li>
  106. <li class="toctree-l2"><a class="reference internal" href="../libraries/ftp.html">FTP Class</a></li>
  107. <li class="toctree-l2"><a class="reference internal" href="../libraries/image_lib.html">Image Manipulation Class</a></li>
  108. <li class="toctree-l2"><a class="reference internal" href="../libraries/input.html">Input Class</a></li>
  109. <li class="toctree-l2"><a class="reference internal" href="../libraries/javascript.html">Javascript Class</a></li>
  110. <li class="toctree-l2"><a class="reference internal" href="../libraries/language.html">Language Class</a></li>
  111. <li class="toctree-l2"><a class="reference internal" href="../libraries/loader.html">Loader Class</a></li>
  112. <li class="toctree-l2"><a class="reference internal" href="../libraries/migration.html">Migrations Class</a></li>
  113. <li class="toctree-l2"><a class="reference internal" href="../libraries/output.html">Output Class</a></li>
  114. <li class="toctree-l2"><a class="reference internal" href="../libraries/pagination.html">Pagination Class</a></li>
  115. <li class="toctree-l2"><a class="reference internal" href="../libraries/parser.html">Template Parser Class</a></li>
  116. <li class="toctree-l2"><a class="reference internal" href="../libraries/security.html">Security Class</a></li>
  117. <li class="toctree-l2"><a class="reference internal" href="../libraries/sessions.html">Session Library</a></li>
  118. <li class="toctree-l2"><a class="reference internal" href="../libraries/table.html">HTML Table Class</a></li>
  119. <li class="toctree-l2"><a class="reference internal" href="../libraries/trackback.html">Trackback Class</a></li>
  120. <li class="toctree-l2"><a class="reference internal" href="../libraries/typography.html">Typography Class</a></li>
  121. <li class="toctree-l2"><a class="reference internal" href="../libraries/unit_testing.html">Unit Testing Class</a></li>
  122. <li class="toctree-l2"><a class="reference internal" href="../libraries/uri.html">URI Class</a></li>
  123. <li class="toctree-l2"><a class="reference internal" href="../libraries/user_agent.html">User Agent Class</a></li>
  124. <li class="toctree-l2"><a class="reference internal" href="../libraries/xmlrpc.html">XML-RPC and XML-RPC Server Classes</a></li>
  125. <li class="toctree-l2"><a class="reference internal" href="../libraries/zip.html">Zip Encoding Class</a></li>
  126. </ul>
  127. </li>
  128. </ul>
  129. <ul>
  130. <li class="toctree-l1"><a class="reference internal" href="../database/index.html">Database Reference</a><ul>
  131. <li class="toctree-l2"><a class="reference internal" href="../database/examples.html">Quick Start: Usage Examples</a></li>
  132. <li class="toctree-l2"><a class="reference internal" href="../database/configuration.html">Database Configuration</a></li>
  133. <li class="toctree-l2"><a class="reference internal" href="../database/connecting.html">Connecting to a Database</a></li>
  134. <li class="toctree-l2"><a class="reference internal" href="../database/queries.html">Running Queries</a></li>
  135. <li class="toctree-l2"><a class="reference internal" href="../database/results.html">Generating Query Results</a></li>
  136. <li class="toctree-l2"><a class="reference internal" href="../database/helpers.html">Query Helper Functions</a></li>
  137. <li class="toctree-l2"><a class="reference internal" href="../database/query_builder.html">Query Builder Class</a></li>
  138. <li class="toctree-l2"><a class="reference internal" href="../database/transactions.html">Transactions</a></li>
  139. <li class="toctree-l2"><a class="reference internal" href="../database/metadata.html">Getting MetaData</a></li>
  140. <li class="toctree-l2"><a class="reference internal" href="../database/call_function.html">Custom Function Calls</a></li>
  141. <li class="toctree-l2"><a class="reference internal" href="../database/caching.html">Query Caching</a></li>
  142. <li class="toctree-l2"><a class="reference internal" href="../database/forge.html">Database Manipulation with Database Forge</a></li>
  143. <li class="toctree-l2"><a class="reference internal" href="../database/utilities.html">Database Utilities Class</a></li>
  144. <li class="toctree-l2"><a class="reference internal" href="../database/db_driver_reference.html">Database Driver Reference</a></li>
  145. </ul>
  146. </li>
  147. </ul>
  148. <ul>
  149. <li class="toctree-l1"><a class="reference internal" href="../helpers/index.html">Helpers</a><ul>
  150. <li class="toctree-l2"><a class="reference internal" href="../helpers/array_helper.html">Array Helper</a></li>
  151. <li class="toctree-l2"><a class="reference internal" href="../helpers/captcha_helper.html">CAPTCHA Helper</a></li>
  152. <li class="toctree-l2"><a class="reference internal" href="../helpers/cookie_helper.html">Cookie Helper</a></li>
  153. <li class="toctree-l2"><a class="reference internal" href="../helpers/date_helper.html">Date Helper</a></li>
  154. <li class="toctree-l2"><a class="reference internal" href="../helpers/directory_helper.html">Directory Helper</a></li>
  155. <li class="toctree-l2"><a class="reference internal" href="../helpers/download_helper.html">Download Helper</a></li>
  156. <li class="toctree-l2"><a class="reference internal" href="../helpers/email_helper.html">Email Helper</a></li>
  157. <li class="toctree-l2"><a class="reference internal" href="../helpers/file_helper.html">File Helper</a></li>
  158. <li class="toctree-l2"><a class="reference internal" href="../helpers/form_helper.html">Form Helper</a></li>
  159. <li class="toctree-l2"><a class="reference internal" href="../helpers/html_helper.html">HTML Helper</a></li>
  160. <li class="toctree-l2"><a class="reference internal" href="../helpers/inflector_helper.html">Inflector Helper</a></li>
  161. <li class="toctree-l2"><a class="reference internal" href="../helpers/language_helper.html">Language Helper</a></li>
  162. <li class="toctree-l2"><a class="reference internal" href="../helpers/number_helper.html">Number Helper</a></li>
  163. <li class="toctree-l2"><a class="reference internal" href="../helpers/path_helper.html">Path Helper</a></li>
  164. <li class="toctree-l2"><a class="reference internal" href="../helpers/security_helper.html">Security Helper</a></li>
  165. <li class="toctree-l2"><a class="reference internal" href="../helpers/smiley_helper.html">Smiley Helper</a></li>
  166. <li class="toctree-l2"><a class="reference internal" href="../helpers/string_helper.html">String Helper</a></li>
  167. <li class="toctree-l2"><a class="reference internal" href="../helpers/text_helper.html">Text Helper</a></li>
  168. <li class="toctree-l2"><a class="reference internal" href="../helpers/typography_helper.html">Typography Helper</a></li>
  169. <li class="toctree-l2"><a class="reference internal" href="../helpers/url_helper.html">URL Helper</a></li>
  170. <li class="toctree-l2"><a class="reference internal" href="../helpers/xml_helper.html">XML Helper</a></li>
  171. </ul>
  172. </li>
  173. </ul>
  174. </div>
  175. </div>
  176. </div>
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  180. </a>
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  184. <div class="wy-side-nav-search">
  185. <a href="../index.html" class="fa fa-home"> CodeIgniter</a>
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  196. <li class="toctree-l1"><a class="reference internal" href="welcome.html">Welcome to CodeIgniter</a></li>
  197. </ul>
  198. <ul>
  199. <li class="toctree-l1"><a class="reference internal" href="../installation/index.html">Installation Instructions</a><ul>
  200. <li class="toctree-l2"><a class="reference internal" href="../installation/downloads.html">Downloading CodeIgniter</a></li>
  201. <li class="toctree-l2"><a class="reference internal" href="../installation/index.html">Installation Instructions</a></li>
  202. <li class="toctree-l2"><a class="reference internal" href="../installation/upgrading.html">Upgrading From a Previous Version</a></li>
  203. <li class="toctree-l2"><a class="reference internal" href="../installation/troubleshooting.html">Troubleshooting</a></li>
  204. </ul>
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  208. <li class="toctree-l1"><a class="reference internal" href="../overview/index.html">CodeIgniter Overview</a><ul>
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  210. <li class="toctree-l2"><a class="reference internal" href="../overview/at_a_glance.html">CodeIgniter at a Glance</a></li>
  211. <li class="toctree-l2"><a class="reference internal" href="../overview/features.html">Supported Features</a></li>
  212. <li class="toctree-l2"><a class="reference internal" href="../overview/appflow.html">Application Flow Chart</a></li>
  213. <li class="toctree-l2"><a class="reference internal" href="../overview/mvc.html">Model-View-Controller</a></li>
  214. <li class="toctree-l2"><a class="reference internal" href="../overview/goals.html">Architectural Goals</a></li>
  215. </ul>
  216. </li>
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  218. <ul>
  219. <li class="toctree-l1"><a class="reference internal" href="../tutorial/index.html">Tutorial</a><ul>
  220. <li class="toctree-l2"><a class="reference internal" href="../tutorial/static_pages.html">Static pages</a></li>
  221. <li class="toctree-l2"><a class="reference internal" href="../tutorial/news_section.html">News section</a></li>
  222. <li class="toctree-l2"><a class="reference internal" href="../tutorial/create_news_items.html">Create news items</a></li>
  223. <li class="toctree-l2"><a class="reference internal" href="../tutorial/conclusion.html">Conclusion</a></li>
  224. </ul>
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  228. <li class="toctree-l1"><a class="reference internal" href="../contributing/index.html">Contributing to CodeIgniter</a><ul>
  229. <li class="toctree-l2"><a class="reference internal" href="../documentation/index.html">Writing CodeIgniter Documentation</a></li>
  230. <li class="toctree-l2"><a class="reference internal" href="../DCO.html">Developer’s Certificate of Origin 1.1</a></li>
  231. </ul>
  232. </li>
  233. </ul>
  234. <ul class="current">
  235. <li class="toctree-l1 current"><a class="reference internal" href="index.html">General Topics</a><ul class="current">
  236. <li class="toctree-l2"><a class="reference internal" href="urls.html">CodeIgniter URLs</a></li>
  237. <li class="toctree-l2"><a class="reference internal" href="controllers.html">Controllers</a></li>
  238. <li class="toctree-l2"><a class="reference internal" href="reserved_names.html">Reserved Names</a></li>
  239. <li class="toctree-l2"><a class="reference internal" href="views.html">Views</a></li>
  240. <li class="toctree-l2"><a class="reference internal" href="models.html">Models</a></li>
  241. <li class="toctree-l2"><a class="reference internal" href="helpers.html">Helpers</a></li>
  242. <li class="toctree-l2"><a class="reference internal" href="libraries.html">Using CodeIgniter Libraries</a></li>
  243. <li class="toctree-l2 current"><a class="current reference internal" href="#">Creating Libraries</a></li>
  244. <li class="toctree-l2"><a class="reference internal" href="drivers.html">Using CodeIgniter Drivers</a></li>
  245. <li class="toctree-l2"><a class="reference internal" href="creating_drivers.html">Creating Drivers</a></li>
  246. <li class="toctree-l2"><a class="reference internal" href="core_classes.html">Creating Core System Classes</a></li>
  247. <li class="toctree-l2"><a class="reference internal" href="ancillary_classes.html">Creating Ancillary Classes</a></li>
  248. <li class="toctree-l2"><a class="reference internal" href="hooks.html">Hooks - Extending the Framework Core</a></li>
  249. <li class="toctree-l2"><a class="reference internal" href="autoloader.html">Auto-loading Resources</a></li>
  250. <li class="toctree-l2"><a class="reference internal" href="common_functions.html">Common Functions</a></li>
  251. <li class="toctree-l2"><a class="reference internal" href="compatibility_functions.html">Compatibility Functions</a></li>
  252. <li class="toctree-l2"><a class="reference internal" href="routing.html">URI Routing</a></li>
  253. <li class="toctree-l2"><a class="reference internal" href="errors.html">Error Handling</a></li>
  254. <li class="toctree-l2"><a class="reference internal" href="caching.html">Caching</a></li>
  255. <li class="toctree-l2"><a class="reference internal" href="profiling.html">Profiling Your Application</a></li>
  256. <li class="toctree-l2"><a class="reference internal" href="cli.html">Running via the CLI</a></li>
  257. <li class="toctree-l2"><a class="reference internal" href="managing_apps.html">Managing your Applications</a></li>
  258. <li class="toctree-l2"><a class="reference internal" href="environments.html">Handling Multiple Environments</a></li>
  259. <li class="toctree-l2"><a class="reference internal" href="alternative_php.html">Alternate PHP Syntax for View Files</a></li>
  260. <li class="toctree-l2"><a class="reference internal" href="security.html">Security</a></li>
  261. <li class="toctree-l2"><a class="reference internal" href="styleguide.html">PHP Style Guide</a></li>
  262. </ul>
  263. </li>
  264. </ul>
  265. <ul>
  266. <li class="toctree-l1"><a class="reference internal" href="../libraries/index.html">Libraries</a><ul>
  267. <li class="toctree-l2"><a class="reference internal" href="../libraries/benchmark.html">Benchmarking Class</a></li>
  268. <li class="toctree-l2"><a class="reference internal" href="../libraries/caching.html">Caching Driver</a></li>
  269. <li class="toctree-l2"><a class="reference internal" href="../libraries/calendar.html">Calendaring Class</a></li>
  270. <li class="toctree-l2"><a class="reference internal" href="../libraries/cart.html">Shopping Cart Class</a></li>
  271. <li class="toctree-l2"><a class="reference internal" href="../libraries/config.html">Config Class</a></li>
  272. <li class="toctree-l2"><a class="reference internal" href="../libraries/email.html">Email Class</a></li>
  273. <li class="toctree-l2"><a class="reference internal" href="../libraries/encrypt.html">Encrypt Class</a></li>
  274. <li class="toctree-l2"><a class="reference internal" href="../libraries/encryption.html">Encryption Library</a></li>
  275. <li class="toctree-l2"><a class="reference internal" href="../libraries/file_uploading.html">File Uploading Class</a></li>
  276. <li class="toctree-l2"><a class="reference internal" href="../libraries/form_validation.html">Form Validation</a></li>
  277. <li class="toctree-l2"><a class="reference internal" href="../libraries/ftp.html">FTP Class</a></li>
  278. <li class="toctree-l2"><a class="reference internal" href="../libraries/image_lib.html">Image Manipulation Class</a></li>
  279. <li class="toctree-l2"><a class="reference internal" href="../libraries/input.html">Input Class</a></li>
  280. <li class="toctree-l2"><a class="reference internal" href="../libraries/javascript.html">Javascript Class</a></li>
  281. <li class="toctree-l2"><a class="reference internal" href="../libraries/language.html">Language Class</a></li>
  282. <li class="toctree-l2"><a class="reference internal" href="../libraries/loader.html">Loader Class</a></li>
  283. <li class="toctree-l2"><a class="reference internal" href="../libraries/migration.html">Migrations Class</a></li>
  284. <li class="toctree-l2"><a class="reference internal" href="../libraries/output.html">Output Class</a></li>
  285. <li class="toctree-l2"><a class="reference internal" href="../libraries/pagination.html">Pagination Class</a></li>
  286. <li class="toctree-l2"><a class="reference internal" href="../libraries/parser.html">Template Parser Class</a></li>
  287. <li class="toctree-l2"><a class="reference internal" href="../libraries/security.html">Security Class</a></li>
  288. <li class="toctree-l2"><a class="reference internal" href="../libraries/sessions.html">Session Library</a></li>
  289. <li class="toctree-l2"><a class="reference internal" href="../libraries/table.html">HTML Table Class</a></li>
  290. <li class="toctree-l2"><a class="reference internal" href="../libraries/trackback.html">Trackback Class</a></li>
  291. <li class="toctree-l2"><a class="reference internal" href="../libraries/typography.html">Typography Class</a></li>
  292. <li class="toctree-l2"><a class="reference internal" href="../libraries/unit_testing.html">Unit Testing Class</a></li>
  293. <li class="toctree-l2"><a class="reference internal" href="../libraries/uri.html">URI Class</a></li>
  294. <li class="toctree-l2"><a class="reference internal" href="../libraries/user_agent.html">User Agent Class</a></li>
  295. <li class="toctree-l2"><a class="reference internal" href="../libraries/xmlrpc.html">XML-RPC and XML-RPC Server Classes</a></li>
  296. <li class="toctree-l2"><a class="reference internal" href="../libraries/zip.html">Zip Encoding Class</a></li>
  297. </ul>
  298. </li>
  299. </ul>
  300. <ul>
  301. <li class="toctree-l1"><a class="reference internal" href="../database/index.html">Database Reference</a><ul>
  302. <li class="toctree-l2"><a class="reference internal" href="../database/examples.html">Quick Start: Usage Examples</a></li>
  303. <li class="toctree-l2"><a class="reference internal" href="../database/configuration.html">Database Configuration</a></li>
  304. <li class="toctree-l2"><a class="reference internal" href="../database/connecting.html">Connecting to a Database</a></li>
  305. <li class="toctree-l2"><a class="reference internal" href="../database/queries.html">Running Queries</a></li>
  306. <li class="toctree-l2"><a class="reference internal" href="../database/results.html">Generating Query Results</a></li>
  307. <li class="toctree-l2"><a class="reference internal" href="../database/helpers.html">Query Helper Functions</a></li>
  308. <li class="toctree-l2"><a class="reference internal" href="../database/query_builder.html">Query Builder Class</a></li>
  309. <li class="toctree-l2"><a class="reference internal" href="../database/transactions.html">Transactions</a></li>
  310. <li class="toctree-l2"><a class="reference internal" href="../database/metadata.html">Getting MetaData</a></li>
  311. <li class="toctree-l2"><a class="reference internal" href="../database/call_function.html">Custom Function Calls</a></li>
  312. <li class="toctree-l2"><a class="reference internal" href="../database/caching.html">Query Caching</a></li>
  313. <li class="toctree-l2"><a class="reference internal" href="../database/forge.html">Database Manipulation with Database Forge</a></li>
  314. <li class="toctree-l2"><a class="reference internal" href="../database/utilities.html">Database Utilities Class</a></li>
  315. <li class="toctree-l2"><a class="reference internal" href="../database/db_driver_reference.html">Database Driver Reference</a></li>
  316. </ul>
  317. </li>
  318. </ul>
  319. <ul>
  320. <li class="toctree-l1"><a class="reference internal" href="../helpers/index.html">Helpers</a><ul>
  321. <li class="toctree-l2"><a class="reference internal" href="../helpers/array_helper.html">Array Helper</a></li>
  322. <li class="toctree-l2"><a class="reference internal" href="../helpers/captcha_helper.html">CAPTCHA Helper</a></li>
  323. <li class="toctree-l2"><a class="reference internal" href="../helpers/cookie_helper.html">Cookie Helper</a></li>
  324. <li class="toctree-l2"><a class="reference internal" href="../helpers/date_helper.html">Date Helper</a></li>
  325. <li class="toctree-l2"><a class="reference internal" href="../helpers/directory_helper.html">Directory Helper</a></li>
  326. <li class="toctree-l2"><a class="reference internal" href="../helpers/download_helper.html">Download Helper</a></li>
  327. <li class="toctree-l2"><a class="reference internal" href="../helpers/email_helper.html">Email Helper</a></li>
  328. <li class="toctree-l2"><a class="reference internal" href="../helpers/file_helper.html">File Helper</a></li>
  329. <li class="toctree-l2"><a class="reference internal" href="../helpers/form_helper.html">Form Helper</a></li>
  330. <li class="toctree-l2"><a class="reference internal" href="../helpers/html_helper.html">HTML Helper</a></li>
  331. <li class="toctree-l2"><a class="reference internal" href="../helpers/inflector_helper.html">Inflector Helper</a></li>
  332. <li class="toctree-l2"><a class="reference internal" href="../helpers/language_helper.html">Language Helper</a></li>
  333. <li class="toctree-l2"><a class="reference internal" href="../helpers/number_helper.html">Number Helper</a></li>
  334. <li class="toctree-l2"><a class="reference internal" href="../helpers/path_helper.html">Path Helper</a></li>
  335. <li class="toctree-l2"><a class="reference internal" href="../helpers/security_helper.html">Security Helper</a></li>
  336. <li class="toctree-l2"><a class="reference internal" href="../helpers/smiley_helper.html">Smiley Helper</a></li>
  337. <li class="toctree-l2"><a class="reference internal" href="../helpers/string_helper.html">String Helper</a></li>
  338. <li class="toctree-l2"><a class="reference internal" href="../helpers/text_helper.html">Text Helper</a></li>
  339. <li class="toctree-l2"><a class="reference internal" href="../helpers/typography_helper.html">Typography Helper</a></li>
  340. <li class="toctree-l2"><a class="reference internal" href="../helpers/url_helper.html">URL Helper</a></li>
  341. <li class="toctree-l2"><a class="reference internal" href="../helpers/xml_helper.html">XML Helper</a></li>
  342. </ul>
  343. </li>
  344. </ul>
  345. </div>
  346. &nbsp;
  347. </nav>
  348. <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap">
  349. <nav class="wy-nav-top" role="navigation" aria-label="top navigation">
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  351. <a href="../index.html">CodeIgniter</a>
  352. </nav>
  353. <div class="wy-nav-content">
  354. <div class="rst-content">
  355. <div role="navigation" aria-label="breadcrumbs navigation">
  356. <ul class="wy-breadcrumbs">
  357. <li><a href="../index.html">Docs</a> &raquo;</li>
  358. <li><a href="index.html">General Topics</a> &raquo;</li>
  359. <li>Creating Libraries</li>
  360. <li class="wy-breadcrumbs-aside">
  361. </li>
  362. <div style="float:right;margin-left:5px;" id="closeMe">
  363. <img title="Classic Layout" alt="classic layout" src="data:image/gif;base64,R0lGODlhFAAUAJEAAAAAADMzM////wAAACH5BAUUAAIALAAAAAAUABQAAAImlI+py+0PU5gRBRDM3DxbWoXis42X13USOLauUIqnlsaH/eY6UwAAOw==" />
  364. </div>
  365. </ul>
  366. <hr/>
  367. </div>
  368. <div role="main" class="document">
  369. <div class="section" id="creating-libraries">
  370. <h1>Creating Libraries<a class="headerlink" href="#creating-libraries" title="Permalink to this headline">¶</a></h1>
  371. <p>When we use the term “Libraries” we are normally referring to the
  372. classes that are located in the libraries directory and described in the
  373. Class Reference of this user guide. In this case, however, we will
  374. instead describe how you can create your own libraries within your
  375. application/libraries directory in order to maintain separation between
  376. your local resources and the global framework resources.</p>
  377. <p>As an added bonus, CodeIgniter permits your libraries to extend native
  378. classes if you simply need to add some functionality to an existing
  379. library. Or you can even replace native libraries just by placing
  380. identically named versions in your <em>application/libraries</em> directory.</p>
  381. <p>In summary:</p>
  382. <ul class="simple">
  383. <li>You can create entirely new libraries.</li>
  384. <li>You can extend native libraries.</li>
  385. <li>You can replace native libraries.</li>
  386. </ul>
  387. <p>The page below explains these three concepts in detail.</p>
  388. <div class="admonition note">
  389. <p class="first admonition-title">Note</p>
  390. <p class="last">The Database classes can not be extended or replaced with your
  391. own classes. All other classes are able to be replaced/extended.</p>
  392. </div>
  393. <div class="section" id="storage">
  394. <h2>Storage<a class="headerlink" href="#storage" title="Permalink to this headline">¶</a></h2>
  395. <p>Your library classes should be placed within your <em>application/libraries</em>
  396. directory, as this is where CodeIgniter will look for them when they are
  397. initialized.</p>
  398. </div>
  399. <div class="section" id="naming-conventions">
  400. <h2>Naming Conventions<a class="headerlink" href="#naming-conventions" title="Permalink to this headline">¶</a></h2>
  401. <ul class="simple">
  402. <li>File names must be capitalized. For example: Myclass.php</li>
  403. <li>Class declarations must be capitalized. For example: class Myclass</li>
  404. <li>Class names and file names must match.</li>
  405. </ul>
  406. </div>
  407. <div class="section" id="the-class-file">
  408. <h2>The Class File<a class="headerlink" href="#the-class-file" title="Permalink to this headline">¶</a></h2>
  409. <p>Classes should have this basic prototype:</p>
  410. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span>
  411. <span class="nb">defined</span><span class="p">(</span><span class="s1">&#39;BASEPATH&#39;</span><span class="p">)</span> <span class="k">OR</span> <span class="k">exit</span><span class="p">(</span><span class="s1">&#39;No direct script access allowed&#39;</span><span class="p">);</span>
  412. <span class="k">class</span> <span class="nc">Someclass</span> <span class="p">{</span>
  413. <span class="k">public</span> <span class="k">function</span> <span class="nf">some_method</span><span class="p">()</span>
  414. <span class="p">{</span>
  415. <span class="p">}</span>
  416. <span class="p">}</span>
  417. </pre></div>
  418. </div>
  419. <div class="admonition note">
  420. <p class="first admonition-title">Note</p>
  421. <p class="last">We are using the name Someclass purely as an example.</p>
  422. </div>
  423. </div>
  424. <div class="section" id="using-your-class">
  425. <h2>Using Your Class<a class="headerlink" href="#using-your-class" title="Permalink to this headline">¶</a></h2>
  426. <p>From within any of your <a class="reference internal" href="controllers.html"><span class="doc">Controller</span></a> methods you
  427. can initialize your class using the standard:</p>
  428. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">library</span><span class="p">(</span><span class="s1">&#39;someclass&#39;</span><span class="p">);</span>
  429. </pre></div>
  430. </div>
  431. <p>Where <em>someclass</em> is the file name, without the “.php” file extension.
  432. You can submit the file name capitalized or lower case. CodeIgniter
  433. doesn’t care.</p>
  434. <p>Once loaded you can access your class using the lower case version:</p>
  435. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">someclass</span><span class="o">-&gt;</span><span class="na">some_method</span><span class="p">();</span><span class="nx"> </span> <span class="c1">// Object instances will always be lower case</span>
  436. </pre></div>
  437. </div>
  438. </div>
  439. <div class="section" id="passing-parameters-when-initializing-your-class">
  440. <h2>Passing Parameters When Initializing Your Class<a class="headerlink" href="#passing-parameters-when-initializing-your-class" title="Permalink to this headline">¶</a></h2>
  441. <p>In the library loading method you can dynamically pass data as an
  442. array via the second parameter and it will be passed to your class
  443. constructor:</p>
  444. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$params</span> <span class="o">=</span> <span class="k">array</span><span class="p">(</span><span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;large&#39;</span><span class="p">,</span> <span class="s1">&#39;color&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;red&#39;</span><span class="p">);</span>
  445. <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">library</span><span class="p">(</span><span class="s1">&#39;someclass&#39;</span><span class="p">,</span> <span class="nv">$params</span><span class="p">);</span>
  446. </pre></div>
  447. </div>
  448. <p>If you use this feature you must set up your class constructor to expect
  449. data:</p>
  450. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="nb">defined</span><span class="p">(</span><span class="s1">&#39;BASEPATH&#39;</span><span class="p">)</span> <span class="k">OR</span> <span class="k">exit</span><span class="p">(</span><span class="s1">&#39;No direct script access allowed&#39;</span><span class="p">);</span>
  451. <span class="k">class</span> <span class="nc">Someclass</span> <span class="p">{</span>
  452. <span class="k">public</span> <span class="k">function</span> <span class="nf">__construct</span><span class="p">(</span><span class="nv">$params</span><span class="p">)</span>
  453. <span class="p">{</span>
  454. <span class="c1">// Do something with $params</span>
  455. <span class="p">}</span>
  456. <span class="p">}</span>
  457. </pre></div>
  458. </div>
  459. <p>You can also pass parameters stored in a config file. Simply create a
  460. config file named identically to the class file name and store it in
  461. your <em>application/config/</em> directory. Note that if you dynamically pass
  462. parameters as described above, the config file option will not be
  463. available.</p>
  464. </div>
  465. <div class="section" id="utilizing-codeigniter-resources-within-your-library">
  466. <h2>Utilizing CodeIgniter Resources within Your Library<a class="headerlink" href="#utilizing-codeigniter-resources-within-your-library" title="Permalink to this headline">¶</a></h2>
  467. <p>To access CodeIgniter’s native resources within your library use the
  468. <code class="docutils literal"><span class="pre">get_instance()</span></code> method. This method returns the CodeIgniter super
  469. object.</p>
  470. <p>Normally from within your controller methods you will call any of the
  471. available CodeIgniter methods using the <code class="docutils literal"><span class="pre">$this</span></code> construct:</p>
  472. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">helper</span><span class="p">(</span><span class="s1">&#39;url&#39;</span><span class="p">);</span>
  473. <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">library</span><span class="p">(</span><span class="s1">&#39;session&#39;</span><span class="p">);</span>
  474. <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">config</span><span class="o">-&gt;</span><span class="na">item</span><span class="p">(</span><span class="s1">&#39;base_url&#39;</span><span class="p">);</span>
  475. <span class="c1">// etc.</span>
  476. </pre></div>
  477. </div>
  478. <p><code class="docutils literal"><span class="pre">$this</span></code>, however, only works directly within your controllers, your
  479. models, or your views. If you would like to use CodeIgniter’s classes
  480. from within your own custom classes you can do so as follows:</p>
  481. <p>First, assign the CodeIgniter object to a variable:</p>
  482. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$CI</span> <span class="o">=&amp;</span> <span class="nx">get_instance</span><span class="p">();</span>
  483. </pre></div>
  484. </div>
  485. <p>Once you’ve assigned the object to a variable, you’ll use that variable
  486. <em>instead</em> of <code class="docutils literal"><span class="pre">$this</span></code>:</p>
  487. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$CI</span> <span class="o">=&amp;</span> <span class="nx">get_instance</span><span class="p">();</span>
  488. <span class="nv">$CI</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">helper</span><span class="p">(</span><span class="s1">&#39;url&#39;</span><span class="p">);</span>
  489. <span class="nv">$CI</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">library</span><span class="p">(</span><span class="s1">&#39;session&#39;</span><span class="p">);</span>
  490. <span class="nv">$CI</span><span class="o">-&gt;</span><span class="na">config</span><span class="o">-&gt;</span><span class="na">item</span><span class="p">(</span><span class="s1">&#39;base_url&#39;</span><span class="p">);</span>
  491. <span class="c1">// etc.</span>
  492. </pre></div>
  493. </div>
  494. <div class="admonition note">
  495. <p class="first admonition-title">Note</p>
  496. <p>You’ll notice that the above <code class="docutils literal"><span class="pre">get_instance()</span></code> function is being
  497. passed by reference:</p>
  498. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$CI</span> <span class="o">=&amp;</span> <span class="nx">get_instance</span><span class="p">();</span>
  499. </pre></div>
  500. </div>
  501. <p class="last">This is very important. Assigning by reference allows you to use the
  502. original CodeIgniter object rather than creating a copy of it.</p>
  503. </div>
  504. <p>However, since a library is a class, it would be better if you
  505. take full advantage of the OOP principles. So, in order to
  506. be able to use the CodeIgniter super-object in all of the class
  507. methods, you’re encouraged to assign it to a property instead:</p>
  508. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">Example_library</span> <span class="p">{</span>
  509. <span class="k">protected</span> <span class="nv">$CI</span><span class="p">;</span>
  510. <span class="c1">// We&#39;ll use a constructor, as you can&#39;t directly call a function</span>
  511. <span class="c1">// from a property definition.</span>
  512. <span class="k">public</span> <span class="k">function</span> <span class="nf">__construct</span><span class="p">()</span>
  513. <span class="p">{</span>
  514. <span class="c1">// Assign the CodeIgniter super-object</span>
  515. <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">CI</span> <span class="o">=&amp;</span> <span class="nx">get_instance</span><span class="p">();</span>
  516. <span class="p">}</span>
  517. <span class="k">public</span> <span class="k">function</span> <span class="nf">foo</span><span class="p">()</span>
  518. <span class="p">{</span>
  519. <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">CI</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">helper</span><span class="p">(</span><span class="s1">&#39;url&#39;</span><span class="p">);</span>
  520. <span class="nx">redirect</span><span class="p">();</span>
  521. <span class="p">}</span>
  522. <span class="k">public</span> <span class="k">function</span> <span class="nf">bar</span><span class="p">()</span>
  523. <span class="p">{</span>
  524. <span class="k">echo</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">CI</span><span class="o">-&gt;</span><span class="na">config</span><span class="o">-&gt;</span><span class="na">item</span><span class="p">(</span><span class="s1">&#39;base_url&#39;</span><span class="p">);</span>
  525. <span class="p">}</span>
  526. <span class="p">}</span>
  527. </pre></div>
  528. </div>
  529. </div>
  530. <div class="section" id="replacing-native-libraries-with-your-versions">
  531. <h2>Replacing Native Libraries with Your Versions<a class="headerlink" href="#replacing-native-libraries-with-your-versions" title="Permalink to this headline">¶</a></h2>
  532. <p>Simply by naming your class files identically to a native library will
  533. cause CodeIgniter to use it instead of the native one. To use this
  534. feature you must name the file and the class declaration exactly the
  535. same as the native library. For example, to replace the native Email
  536. library you’ll create a file named <em>application/libraries/Email.php</em>,
  537. and declare your class with:</p>
  538. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">CI_Email</span> <span class="p">{</span>
  539. <span class="p">}</span>
  540. </pre></div>
  541. </div>
  542. <p>Note that most native classes are prefixed with CI_.</p>
  543. <p>To load your library you’ll see the standard loading method:</p>
  544. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">library</span><span class="p">(</span><span class="s1">&#39;email&#39;</span><span class="p">);</span>
  545. </pre></div>
  546. </div>
  547. <div class="admonition note">
  548. <p class="first admonition-title">Note</p>
  549. <p class="last">At this time the Database classes can not be replaced with
  550. your own versions.</p>
  551. </div>
  552. </div>
  553. <div class="section" id="extending-native-libraries">
  554. <h2>Extending Native Libraries<a class="headerlink" href="#extending-native-libraries" title="Permalink to this headline">¶</a></h2>
  555. <p>If all you need to do is add some functionality to an existing library -
  556. perhaps add a method or two - then it’s overkill to replace the entire
  557. library with your version. In this case it’s better to simply extend the
  558. class. Extending a class is nearly identical to replacing a class with a
  559. couple exceptions:</p>
  560. <ul class="simple">
  561. <li>The class declaration must extend the parent class.</li>
  562. <li>Your new class name and filename must be prefixed with MY_ (this
  563. item is configurable. See below.).</li>
  564. </ul>
  565. <p>For example, to extend the native Email class you’ll create a file named
  566. <em>application/libraries/MY_Email.php</em>, and declare your class with:</p>
  567. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">MY_Email</span> <span class="k">extends</span> <span class="nx">CI_Email</span> <span class="p">{</span>
  568. <span class="p">}</span>
  569. </pre></div>
  570. </div>
  571. <p>If you need to use a constructor in your class make sure you
  572. extend the parent constructor:</p>
  573. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">MY_Email</span> <span class="k">extends</span> <span class="nx">CI_Email</span> <span class="p">{</span>
  574. <span class="k">public</span> <span class="k">function</span> <span class="nf">__construct</span><span class="p">(</span><span class="nv">$config</span> <span class="o">=</span> <span class="k">array</span><span class="p">())</span>
  575. <span class="p">{</span>
  576. <span class="k">parent</span><span class="o">::</span><span class="na">__construct</span><span class="p">(</span><span class="nv">$config</span><span class="p">);</span>
  577. <span class="c1">// Your own constructor code</span>
  578. <span class="p">}</span>
  579. <span class="p">}</span>
  580. </pre></div>
  581. </div>
  582. <div class="admonition note">
  583. <p class="first admonition-title">Note</p>
  584. <p class="last">Not all of the libraries have the same (or any) parameters
  585. in their constructor. Take a look at the library that you’re
  586. extending first to see how it should be implemented.</p>
  587. </div>
  588. <div class="section" id="loading-your-sub-class">
  589. <h3>Loading Your Sub-class<a class="headerlink" href="#loading-your-sub-class" title="Permalink to this headline">¶</a></h3>
  590. <p>To load your sub-class you’ll use the standard syntax normally used. DO
  591. NOT include your prefix. For example, to load the example above, which
  592. extends the Email class, you will use:</p>
  593. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">library</span><span class="p">(</span><span class="s1">&#39;email&#39;</span><span class="p">);</span>
  594. </pre></div>
  595. </div>
  596. <p>Once loaded you will use the class variable as you normally would for
  597. the class you are extending. In the case of the email class all calls
  598. will use:</p>
  599. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">email</span><span class="o">-&gt;</span><span class="na">some_method</span><span class="p">();</span>
  600. </pre></div>
  601. </div>
  602. </div>
  603. <div class="section" id="setting-your-own-prefix">
  604. <h3>Setting Your Own Prefix<a class="headerlink" href="#setting-your-own-prefix" title="Permalink to this headline">¶</a></h3>
  605. <p>To set your own sub-class prefix, open your
  606. <em>application/config/config.php</em> file and look for this item:</p>
  607. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$config</span><span class="p">[</span><span class="s1">&#39;subclass_prefix&#39;</span><span class="p">]</span> <span class="o">=</span> <span class="s1">&#39;MY_&#39;</span><span class="p">;</span>
  608. </pre></div>
  609. </div>
  610. <p>Please note that all native CodeIgniter libraries are prefixed with CI_
  611. so DO NOT use that as your prefix.</p>
  612. </div>
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