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diff --git a/user_guide_src/source/libraries/loader.rst b/user_guide_src/source/libraries/loader.rst deleted file mode 100644 index 228d5e478..000000000 --- a/user_guide_src/source/libraries/loader.rst +++ /dev/null @@ -1,461 +0,0 @@ -############ -Loader Class -############ - -Loader, as the name suggests, is used to load elements. These elements -can be libraries (classes) :doc:`View files <../general/views>`, -:doc:`Drivers <../general/drivers>`, -:doc:`Helpers <../general/helpers>`, -:doc:`Models <../general/models>`, or your own files. - -.. note:: This class is initialized automatically by the system so there - is no need to do it manually. - -.. contents:: - :local: - -.. raw:: html - - <div class="custom-index container"></div> - -********************** -Application "Packages" -********************** - -An application package allows for the easy distribution of complete sets -of resources in a single directory, complete with its own libraries, -models, helpers, config, and language files. It is recommended that -these packages be placed in the application/third_party directory. Below -is a sample map of an package directory. - -The following is an example of a directory for an application package -named "Foo Bar". - -:: - - /application/third_party/foo_bar - - config/ - helpers/ - language/ - libraries/ - models/ - -Whatever the purpose of the "Foo Bar" application package, it has its -own config files, helpers, language files, libraries, and models. To use -these resources in your controllers, you first need to tell the Loader -that you are going to be loading resources from a package, by adding the -package path via the ``add_package_path()`` method. - -Package view files ------------------- - -By Default, package view files paths are set when ``add_package_path()`` -is called. View paths are looped through, and once a match is -encountered that view is loaded. - -In this instance, it is possible for view naming collisions within -packages to occur, and possibly the incorrect package being loaded. To -ensure against this, set an optional second parameter of FALSE when -calling ``add_package_path()``. - -:: - - $this->load->add_package_path(APPPATH.'my_app', FALSE); - $this->load->view('my_app_index'); // Loads - $this->load->view('welcome_message'); // Will not load the default welcome_message b/c the second param to add_package_path is FALSE - - // Reset things - $this->load->remove_package_path(APPPATH.'my_app'); - - // Again without the second parameter: - $this->load->add_package_path(APPPATH.'my_app'); - $this->load->view('my_app_index'); // Loads - $this->load->view('welcome_message'); // Loads - -*************** -Class Reference -*************** - -.. php:class:: CI_Loader - - .. php:method:: library($library[, $params = NULL[, $object_name = NULL]]) - - :param mixed $library: Library name as a string or an array with multiple libraries - :param array $params: Optional array of parameters to pass to the loaded library's constructor - :param string $object_name: Optional object name to assign the library to - :returns: CI_Loader instance (method chaining) - :rtype: CI_Loader - - This method is used to load core classes. - - .. note:: We use the terms "class" and "library" interchangeably. - - For example, if you would like to send email with CodeIgniter, the first - step is to load the email class within your controller:: - - $this->load->library('email'); - - Once loaded, the library will be ready for use, using ``$this->email``. - - Library files can be stored in subdirectories within the main - "libraries" directory, or within your personal *application/libraries* - directory. To load a file located in a subdirectory, simply include the - path, relative to the "libraries" directory. For example, if you have - file located at:: - - libraries/flavors/Chocolate.php - - You will load it using:: - - $this->load->library('flavors/chocolate'); - - You may nest the file in as many subdirectories as you want. - - Additionally, multiple libraries can be loaded at the same time by - passing an array of libraries to the load method. - :: - - $this->load->library(array('email', 'table')); - - **Setting options** - - The second (optional) parameter allows you to optionally pass - configuration setting. You will typically pass these as an array:: - - $config = array ( - 'mailtype' => 'html', - 'charset' => 'utf-8, - 'priority' => '1' - ); - - $this->load->library('email', $config); - - Config options can usually also be set via a config file. Each library - is explained in detail in its own page, so please read the information - regarding each one you would like to use. - - Please take note, when multiple libraries are supplied in an array for - the first parameter, each will receive the same parameter information. - - **Assigning a Library to a different object name** - - If the third (optional) parameter is blank, the library will usually be - assigned to an object with the same name as the library. For example, if - the library is named Calendar, it will be assigned to a variable named - ``$this->calendar``. - - If you prefer to set your own class names you can pass its value to the - third parameter:: - - $this->load->library('calendar', NULL, 'my_calendar'); - - // Calendar class is now accessed using: - $this->my_calendar - - Please take note, when multiple libraries are supplied in an array for - the first parameter, this parameter is discarded. - - .. php:method:: driver($library[, $params = NULL[, $object_name]]) - - :param mixed $library: Library name as a string or an array with multiple libraries - :param array $params: Optional array of parameters to pass to the loaded library's constructor - :param string $object_name: Optional object name to assign the library to - :returns: CI_Loader instance (method chaining) - :rtype: CI_Loader - - This method is used to load driver libraries, acts very much like the - ``library()`` method. - - As an example, if you would like to use sessions with CodeIgniter, the first - step is to load the session driver within your controller:: - - $this->load->driver('session'); - - Once loaded, the library will be ready for use, using ``$this->session``. - - Driver files must be stored in a subdirectory within the main - "libraries" directory, or within your personal *application/libraries* - directory. The subdirectory must match the parent class name. Read the - :doc:`Drivers <../general/drivers>` description for details. - - Additionally, multiple driver libraries can be loaded at the same time by - passing an array of drivers to the load method. - :: - - $this->load->driver(array('session', 'cache')); - - **Setting options** - - The second (optional) parameter allows you to optionally pass - configuration settings. You will typically pass these as an array:: - - $config = array( - 'sess_driver' => 'cookie', - 'sess_encrypt_cookie' => true, - 'encryption_key' => 'mysecretkey' - ); - - $this->load->driver('session', $config); - - Config options can usually also be set via a config file. Each library - is explained in detail in its own page, so please read the information - regarding each one you would like to use. - - **Assigning a Driver to a different object name** - - If the third (optional) parameter is blank, the library will be assigned - to an object with the same name as the parent class. For example, if - the library is named Session, it will be assigned to a variable named - ``$this->session``. - - If you prefer to set your own class names you can pass its value to the - third parameter:: - - $this->load->library('session', '', 'my_session'); - - // Session class is now accessed using: - $this->my_session - - .. php:method:: view($view[, $vars = array()[, return = FALSE]]) - - :param string $view: View name - :param array $vars: An associative array of variables - :param bool $return: Whether to return the loaded view - :returns: View content string if $return is set to TRUE, otherwise CI_Loader instance (method chaining) - :rtype: mixed - - This method is used to load your View files. If you haven't read the - :doc:`Views <../general/views>` section of the user guide it is - recommended that you do since it shows you how this method is - typically used. - - The first parameter is required. It is the name of the view file you - would like to load. - - .. note:: The .php file extension does not need to be specified unless - you use something other than .php. - - The second **optional** parameter can take an associative array or an - object as input, which it runs through the PHP - `extract() <http://php.net/extract>`_ function to convert to variables - that can be used in your view files. Again, read the - :doc:`Views <../general/views>` page to learn how this might be useful. - - The third **optional** parameter lets you change the behavior of the - method so that it returns data as a string rather than sending it to - your browser. This can be useful if you want to process the data in some - way. If you set the parameter to TRUE (boolean) it will return data. The - default behavior is FALSE, which sends it to your browser. Remember to - assign it to a variable if you want the data returned:: - - $string = $this->load->view('myfile', '', TRUE); - - .. php:method:: vars($vars[, $val = '']) - - :param mixed $vars: An array of variables or a single variable name - :param mixed $val: Optional variable value - :returns: CI_Loader instance (method chaining) - :rtype: CI_Loader - - This method takes an associative array as input and generates - variables using the PHP `extract() <http://php.net/extract>`_ - function. This method produces the same result as using the second - parameter of the ``$this->load->view()`` method above. The reason you - might want to use this method independently is if you would like to - set some global variables in the constructor of your controller and have - them become available in any view file loaded from any method. You can - have multiple calls to this method. The data get cached and merged - into one array for conversion to variables. - - .. php:method:: get_var($key) - - :param string $key: Variable name key - :returns: Value if key is found, NULL if not - :rtype: mixed - - This method checks the associative array of variables available to - your views. This is useful if for any reason a var is set in a library - or another controller method using ``$this->load->vars()``. - - .. php:method:: get_vars() - - :returns: An array of all assigned view variables - :rtype: array - - This method retrieves all variables available to your views. - - .. php:method:: clear_vars() - - :returns: CI_Loader instance (method chaining) - :rtype: CI_Loader - - Clears cached view variables. - - .. php:method:: model($model[, $name = ''[, $db_conn = FALSE]]) - - :param mixed $model: Model name or an array containing multiple models - :param string $name: Optional object name to assign the model to - :param string $db_conn: Optional database configuration group to load - :returns: CI_Loader instance (method chaining) - :rtype: CI_Loader - - :: - - $this->load->model('model_name'); - - - If your model is located in a subdirectory, include the relative path - from your models directory. For example, if you have a model located at - *application/models/blog/Queries.php* you'll load it using:: - - $this->load->model('blog/queries'); - - If you would like your model assigned to a different object name you can - specify it via the second parameter of the loading method:: - - $this->load->model('model_name', 'fubar'); - $this->fubar->method(); - - .. php:method:: database([$params = ''[, $return = FALSE[, $query_builder = NULL]]]) - - :param mixed $params: Database group name or configuration options - :param bool $return: Whether to return the loaded database object - :param bool $query_builder: Whether to load the Query Builder - :returns: Loaded CI_DB instance or FALSE on failure if $return is set to TRUE, otherwise CI_Loader instance (method chaining) - :rtype: mixed - - This method lets you load the database class. The two parameters are - **optional**. Please see the :doc:`database <../database/index>` - section for more info. - - .. php:method:: dbforge([$db = NULL[, $return = FALSE]]) - - :param object $db: Database object - :param bool $return: Whether to return the Database Forge instance - :returns: Loaded CI_DB_forge instance if $return is set to TRUE, otherwise CI_Loader instance (method chaining) - :rtype: mixed - - Loads the :doc:`Database Forge <../database/forge>` class, please refer - to that manual for more info. - - .. php:method:: dbutil([$db = NULL[, $return = FALSE]]) - - :param object $db: Database object - :param bool $return: Whether to return the Database Utilities instance - :returns: Loaded CI_DB_utility instance if $return is set to TRUE, otherwise CI_Loader instance (method chaining) - :rtype: mixed - - Loads the :doc:`Database Utilities <../database/utilities>` class, please - refer to that manual for more info. - - .. php:method:: helper($helpers) - - :param mixed $helpers: Helper name as a string or an array containing multiple helpers - :returns: CI_Loader instance (method chaining) - :rtype: CI_Loader - - This method loads helper files, where file_name is the name of the - file, without the _helper.php extension. - - .. php:method:: file($path[, $return = FALSE]) - - :param string $path: File path - :param bool $return: Whether to return the loaded file - :returns: File contents if $return is set to TRUE, otherwise CI_Loader instance (method chaining) - :rtype: mixed - - This is a generic file loading method. Supply the filepath and name in - the first parameter and it will open and read the file. By default the - data is sent to your browser, just like a View file, but if you set the - second parameter to boolean TRUE it will instead return the data as a - string. - - .. php:method:: language($files[, $lang = '']) - - :param mixed $files: Language file name or an array of multiple language files - :param string $lang: Language name - :returns: CI_Loader instance (method chaining) - :rtype: CI_Loader - - This method is an alias of the :doc:`language loading - method <language>`: ``$this->lang->load()``. - - .. php:method:: config($file[, $use_sections = FALSE[, $fail_gracefully = FALSE]]) - - :param string $file: Configuration file name - :param bool $use_sections: Whether configuration values should be loaded into their own section - :param bool $fail_gracefully: Whether to just return FALSE in case of failure - :returns: TRUE on success, FALSE on failure - :rtype: bool - - This method is an alias of the :doc:`config file loading - method <config>`: ``$this->config->load()`` - - .. php:method:: is_loaded($class) - - :param string $class: Class name - :returns: Singleton property name if found, FALSE if not - :rtype: mixed - - Allows you to check if a class has already been loaded or not. - - .. note:: The word "class" here refers to libraries and drivers. - - If the requested class has been loaded, the method returns its assigned - name in the CI Super-object and FALSE if it's not:: - - $this->load->library('form_validation'); - $this->load->is_loaded('Form_validation'); // returns 'form_validation' - - $this->load->is_loaded('Nonexistent_library'); // returns FALSE - - .. important:: If you have more than one instance of a class (assigned to - different properties), then the first one will be returned. - - :: - - $this->load->library('form_validation', $config, 'fv'); - $this->load->library('form_validation'); - - $this->load->is_loaded('Form_validation'); // returns 'fv' - - .. php:method:: add_package_path($path[, $view_cascade = TRUE]) - - :param string $path: Path to add - :param bool $view_cascade: Whether to use cascading views - :returns: CI_Loader instance (method chaining) - :rtype: CI_Loader - - Adding a package path instructs the Loader class to prepend a given path - for subsequent requests for resources. As an example, the "Foo Bar" - application package above has a library named Foo_bar.php. In our - controller, we'd do the following:: - - $this->load->add_package_path(APPPATH.'third_party/foo_bar/') - ->library('foo_bar'); - - .. php:method:: remove_package_path([$path = '']) - - :param string $path: Path to remove - :returns: CI_Loader instance (method chaining) - :rtype: CI_Loader - - When your controller is finished using resources from an application - package, and particularly if you have other application packages you - want to work with, you may wish to remove the package path so the Loader - no longer looks in that directory for resources. To remove the last path - added, simply call the method with no parameters. - - Or to remove a specific package path, specify the same path previously - given to ``add_package_path()`` for a package.:: - - $this->load->remove_package_path(APPPATH.'third_party/foo_bar/'); - - .. php:method:: get_package_paths([$include_base = TRUE]) - - :param bool $include_base: Whether to include BASEPATH - :returns: An array of package paths - :rtype: array - - Returns all currently available package paths.
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