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+############
+Loader Class
+############
+
+Loader, as the name suggests, is used to load elements. These elements
+can be libraries (classes) :doc:`View files <../general/views>`,
+: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.
+
+The following functions are available in this class:
+
+$this->load->library('class_name', $config, 'object name')
+===========================================================
+
+This function is used to load core classes. Where class_name is the
+name of the class you want to load. 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->*some_function*().
+
+Library files can be stored in subdirectories within the main
+"libraries" folder, or within your personal application/libraries
+folder. To load a file located in a subdirectory, simply include the
+path, relative to the "libraries" folder. 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 function.
+
+::
+
+	$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', $config);
+
+Config options can usually also be set via a config file. Each library
+is explained in detail in its own page, so please read the information
+regarding each one you would like to use.
+
+Please take note, when multiple libraries are supplied in an array for
+the first parameter, each will receive the same parameter information.
+
+Assigning a Library to a different object name
+----------------------------------------------
+
+If the third (optional) parameter is blank, the library will usually be
+assigned to an object with the same name as the library. For example, if
+the library is named Session, it will be assigned to a variable named
+$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:  $this->my_session 
+
+Please take note, when multiple libraries are supplied in an array for
+the first parameter, this parameter is discarded.
+
+$this->load->view('file_name', $data, true/false)
+==================================================
+
+This function 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 function 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://www.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
+function 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 = $this->load->view('myfile', '', true);
+
+$this->load->model('Model_name');
+==================================
+
+::
+
+	$this->load->model('Model_name');
+
+
+If your model is located in a sub-folder, include the relative path from
+your models folder. 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 function::
+
+	 $this->load->model('Model_name', 'fubar');  $this->fubar->function();
+
+$this->load->database('options', true/false)
+============================================
+
+This function lets you load the database class. The two parameters are
+**optional**. Please see the :doc:`database <../database/index>`
+section for more info.
+
+$this->load->vars($array)
+=========================
+
+This function takes an associative array as input and generates
+variables using the PHP `extract <http://www.php.net/extract>`_
+function. This function produces the same result as using the second
+parameter of the $this->load->view() function above. The reason you
+might want to use this function independently is if you would like to
+set some global variables in the constructor of your controller and have
+them become available in any view file loaded from any function. You can
+have multiple calls to this function. The data get cached and merged
+into one array for conversion to variables.
+
+$this->load->get_var($key)
+===========================
+
+This function 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 $this->load->vars().
+
+$this->load->helper('file_name')
+=================================
+
+This function loads helper files, where file_name is the name of the
+file, without the _helper.php extension.
+
+$this->load->file('filepath/filename', true/false)
+==================================================
+
+This is a generic file loading function. Supply the filepath and name in
+the first parameter and it will open and read the file. By default the
+data is sent to your browser, just like a View file, but if you set the
+second parameter to true (boolean) it will instead return the data as a
+string.
+
+$this->load->language('file_name')
+===================================
+
+This function is an alias of the :doc:`language loading
+function <language>`: $this->lang->load()
+
+$this->load->config('file_name')
+=================================
+
+This function is an alias of the :doc:`config file loading
+function <config>`: $this->config->load()
+
+Application "Packages"
+======================
+
+An application package allows for the easy distribution of complete sets
+of resources in a single directory, complete with its own libraries,
+models, helpers, config, and language files. It is recommended that
+these packages be placed in the application/third_party folder. Below
+is a sample map of an package directory
+
+Sample Package "Foo Bar" Directory Map
+======================================
+
+The following is an example of a directory for an application package
+named "Foo Bar".
+
+::
+
+	/application/third_party/foo_bar  config/ helpers/ language/ libraries/ models/
+
+Whatever the purpose of the "Foo Bar" application package, it has its
+own config files, helpers, language files, libraries, and models. To use
+these resources in your controllers, you first need to tell the Loader
+that you are going to be loading resources from a package, by adding the
+package path.
+
+$this->load->add_package_path()
+---------------------------------
+
+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/'); $this->load->library('foo_bar');
+
+$this->load->remove_package_path()
+------------------------------------
+
+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 folder for resources. To remove the last path
+added, simply call the method with no parameters.
+
+$this->load->remove_package_path()
+------------------------------------
+
+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/');
+
+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', TRUE);
+	$this->load->view('my_app_index'); // Loads
+	$this->load->view('welcome_message'); // Loads
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