From 6c7a4266410070d30f8f6bcdf9c9e67f3d6478e3 Mon Sep 17 00:00:00 2001 From: Andrey Andreev Date: Mon, 19 Jun 2017 11:33:58 +0300 Subject: [ci skip] 3.1.5 release --- user_guide/tutorial/conclusion.html | 516 ++++++++++++++++++++++ user_guide/tutorial/create_news_items.html | 630 ++++++++++++++++++++++++++ user_guide/tutorial/index.html | 526 ++++++++++++++++++++++ user_guide/tutorial/news_section.html | 686 +++++++++++++++++++++++++++++ user_guide/tutorial/static_pages.html | 634 ++++++++++++++++++++++++++ 5 files changed, 2992 insertions(+) create mode 100644 user_guide/tutorial/conclusion.html create mode 100644 user_guide/tutorial/create_news_items.html create mode 100644 user_guide/tutorial/index.html create mode 100644 user_guide/tutorial/news_section.html create mode 100644 user_guide/tutorial/static_pages.html (limited to 'user_guide/tutorial') diff --git a/user_guide/tutorial/conclusion.html b/user_guide/tutorial/conclusion.html new file mode 100644 index 000000000..bc0cf54f9 --- /dev/null +++ b/user_guide/tutorial/conclusion.html @@ -0,0 +1,516 @@ + + + + + + + + + + Conclusion — CodeIgniter 3.1.5 documentation + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ + + + +
+ + + + + + +
+
+
+ +
+
+
+ +
+

Conclusion

+

This tutorial did not cover all of the things you might expect of a +full-fledged content management system, but it introduced you to the +more important topics of routing, writing controllers, and models. We +hope this tutorial gave you an insight into some of CodeIgniter’s basic +design patterns, which you can expand upon.

+

Now that you’ve completed this tutorial, we recommend you check out the +rest of the documentation. CodeIgniter is often praised because of its +comprehensive documentation. Use this to your advantage and read the +“Introduction” and “General Topics” sections thoroughly. You should read +the class and helper references when needed.

+

Every intermediate PHP programmer should be able to get the hang of +CodeIgniter within a few days.

+

If you still have questions about the framework or your own CodeIgniter +code, you can:

+ +
+ + +
+
+ + + + +
+ +
+

+ © Copyright 2014 - 2017, British Columbia Institute of Technology. + Last updated on Jun 19, 2017. +

+
+ + Built with Sphinx using a theme provided by Read the Docs. + +
+
+
+ +
+ +
+ + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file diff --git a/user_guide/tutorial/create_news_items.html b/user_guide/tutorial/create_news_items.html new file mode 100644 index 000000000..1124d32c3 --- /dev/null +++ b/user_guide/tutorial/create_news_items.html @@ -0,0 +1,630 @@ + + + + + + + + + + Create news items — CodeIgniter 3.1.5 documentation + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ + + + +
+ + + + + + +
+
+
+
    +
  • Docs »
    • + +
  • Tutorial »
    • + +
  • Create news items
    • +
  • + +
    • +
    + classic layout +
    +
+
+
+
+ +
+

Create news items

+

You now know how you can read data from a database using CodeIgniter, but +you haven’t written any information to the database yet. In this section +you’ll expand your news controller and model created earlier to include +this functionality.

+
+

Create a form

+

To input data into the database you need to create a form where you can +input the information to be stored. This means you’ll be needing a form +with two fields, one for the title and one for the text. You’ll derive +the slug from our title in the model. Create the new view at +application/views/news/create.php.

+
<h2><?php echo $title; ?></h2>
+
+<?php echo validation_errors(); ?>
+
+<?php echo form_open('news/create'); ?>
+
+    <label for="title">Title</label>
+    <input type="input" name="title" /><br />
+
+    <label for="text">Text</label>
+    <textarea name="text"></textarea><br />
+
+    <input type="submit" name="submit" value="Create news item" />
+
+</form>
+
+
+

There are only two things here that probably look unfamiliar to you: the +form_open() function and the validation_errors() function.

+

The first function is provided by the form +helper and renders the form element and +adds extra functionality, like adding a hidden CSRF prevention +field. The latter is used to report +errors related to form validation.

+

Go back to your news controller. You’re going to do two things here, +check whether the form was submitted and whether the submitted data +passed the validation rules. You’ll use the form +validation library to do this.

+
public function create()
+{
+    $this->load->helper('form');
+    $this->load->library('form_validation');
+
+    $data['title'] = 'Create a news item';
+
+    $this->form_validation->set_rules('title', 'Title', 'required');
+    $this->form_validation->set_rules('text', 'Text', 'required');
+
+    if ($this->form_validation->run() === FALSE)
+    {
+        $this->load->view('templates/header', $data);
+        $this->load->view('news/create');
+        $this->load->view('templates/footer');
+
+    }
+    else
+    {
+        $this->news_model->set_news();
+        $this->load->view('news/success');
+    }
+}
+
+
+

The code above adds a lot of functionality. The first few lines load the +form helper and the form validation library. After that, rules for the +form validation are set. The set_rules() method takes three arguments; +the name of the input field, the name to be used in error messages, and +the rule. In this case the title and text fields are required.

+

CodeIgniter has a powerful form validation library as demonstrated +above. You can read more about this library +here.

+

Continuing down, you can see a condition that checks whether the form +validation ran successfully. If it did not, the form is displayed, if it +was submitted and passed all the rules, the model is called. After +this, a view is loaded to display a success message. Create a view at +application/views/news/success.php and write a success message.

+
+
+

Model

+

The only thing that remains is writing a method that writes the data to +the database. You’ll use the Query Builder class to insert the +information and use the input library to get the posted data. Open up +the model created earlier and add the following:

+
public function set_news()
+{
+    $this->load->helper('url');
+
+    $slug = url_title($this->input->post('title'), 'dash', TRUE);
+
+    $data = array(
+        'title' => $this->input->post('title'),
+        'slug' => $slug,
+        'text' => $this->input->post('text')
+    );
+
+    return $this->db->insert('news', $data);
+}
+
+
+

This new method takes care of inserting the news item into the database. +The third line contains a new function, url_title(). This function - +provided by the URL helper - strips down +the string you pass it, replacing all spaces by dashes (-) and makes +sure everything is in lowercase characters. This leaves you with a nice +slug, perfect for creating URIs.

+

Let’s continue with preparing the record that is going to be inserted +later, inside the $data array. Each element corresponds with a column in +the database table created earlier. You might notice a new method here, +namely the post() method from the input +library. This method makes sure the data is +sanitized, protecting you from nasty attacks from others. The input +library is loaded by default. At last, you insert our $data array into +our database.

+
+
+

Routing

+

Before you can start adding news items into your CodeIgniter application +you have to add an extra rule to config/routes.php file. Make sure your +file contains the following. This makes sure CodeIgniter sees ‘create’ +as a method instead of a news item’s slug.

+
$route['news/create'] = 'news/create';
+$route['news/(:any)'] = 'news/view/$1';
+$route['news'] = 'news';
+$route['(:any)'] = 'pages/view/$1';
+$route['default_controller'] = 'pages/view';
+
+
+

Now point your browser to your local development environment where you +installed CodeIgniter and add index.php/news/create to the URL. +Congratulations, you just created your first CodeIgniter application! +Add some news and check out the different pages you made.

+
+
+ + +
+
+ + + + +
+ +
+

+ © Copyright 2014 - 2017, British Columbia Institute of Technology. + Last updated on Jun 19, 2017. +

+
+ + Built with Sphinx using a theme provided by Read the Docs. + +
+
+
+ +
+ +
+ + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file diff --git a/user_guide/tutorial/index.html b/user_guide/tutorial/index.html new file mode 100644 index 000000000..4511b8cfc --- /dev/null +++ b/user_guide/tutorial/index.html @@ -0,0 +1,526 @@ + + + + + + + + + + Tutorial — CodeIgniter 3.1.5 documentation + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ + + + +
+ + + + + + +
+
+
+
    +
  • Docs »
    • + +
  • Tutorial
    • +
  • + +
    • +
    + classic layout +
    +
+
+
+
+ +
+

Tutorial

+

This tutorial is intended to introduce you to the CodeIgniter framework +and the basic principles of MVC architecture. It will show you how a +basic CodeIgniter application is constructed in step-by-step fashion.

+

In this tutorial, you will be creating a basic news application. You +will begin by writing the code that can load static pages. Next, you +will create a news section that reads news items from a database. +Finally, you’ll add a form to create news items in the database.

+

This tutorial will primarily focus on:

+
    +
  • Model-View-Controller basics
    • +
  • Routing basics
    • +
  • Form validation
    • +
  • Performing basic database queries using “Query Builder”
    • +
+

The entire tutorial is split up over several pages, each explaining a +small part of the functionality of the CodeIgniter framework. You’ll go +through the following pages:

+
    +
  • Introduction, this page, which gives you an overview of what to +expect.
    • +
  • Static pages, which will teach you the basics +of controllers, views and routing.
    • +
  • News section, where you’ll start using models +and will be doing some basic database operations.
    • +
  • Create news items, which will introduce +more advanced database operations and form validation.
    • +
  • Conclusion, which will give you some pointers on +further reading and other resources.
    • +
+

Enjoy your exploration of the CodeIgniter framework.

+
+
+
+ + +
+
+ + + + +
+ +
+

+ © Copyright 2014 - 2017, British Columbia Institute of Technology. + Last updated on Jun 19, 2017. +

+
+ + Built with Sphinx using a theme provided by Read the Docs. + +
+
+
+ +
+ +
+ + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file diff --git a/user_guide/tutorial/news_section.html b/user_guide/tutorial/news_section.html new file mode 100644 index 000000000..b15072712 --- /dev/null +++ b/user_guide/tutorial/news_section.html @@ -0,0 +1,686 @@ + + + + + + + + + + News section — CodeIgniter 3.1.5 documentation + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ + + + +
+ + + + + + +
+
+
+ +
+
+
+ +
+

News section

+

In the last section, we went over some basic concepts of the framework +by writing a class that includes static pages. We cleaned up the URI by +adding custom routing rules. Now it’s time to introduce dynamic content +and start using a database.

+
+

Setting up your model

+

Instead of writing database operations right in the controller, queries +should be placed in a model, so they can easily be reused later. Models +are the place where you retrieve, insert, and update information in your +database or other data stores. They represent your data.

+

Open up the application/models/ directory and create a new file called +News_model.php and add the following code. Make sure you’ve configured +your database properly as described here.

+
<?php
+class News_model extends CI_Model {
+
+        public function __construct()
+        {
+                $this->load->database();
+        }
+}
+
+
+

This code looks similar to the controller code that was used earlier. It +creates a new model by extending CI_Model and loads the database +library. This will make the database class available through the +$this->db object.

+

Before querying the database, a database schema has to be created. +Connect to your database and run the SQL command below (MySQL). +Also add some seed records.

+
CREATE TABLE news (
+        id int(11) NOT NULL AUTO_INCREMENT,
+        title varchar(128) NOT NULL,
+        slug varchar(128) NOT NULL,
+        text text NOT NULL,
+        PRIMARY KEY (id),
+        KEY slug (slug)
+);
+
+
+

Now that the database and a model have been set up, you’ll need a method +to get all of our posts from our database. To do this, the database +abstraction layer that is included with CodeIgniter — +Query Builder — is used. This makes it +possible to write your ‘queries’ once and make them work on all +supported database systems. Add the +following code to your model.

+
public function get_news($slug = FALSE)
+{
+        if ($slug === FALSE)
+        {
+                $query = $this->db->get('news');
+                return $query->result_array();
+        }
+
+        $query = $this->db->get_where('news', array('slug' => $slug));
+        return $query->row_array();
+}
+
+
+

With this code you can perform two different queries. You can get all +news records, or get a news item by its slug. You might have +noticed that the $slug variable wasn’t sanitized before running the +query; Query Builder does this for you.

+
+
+

Display the news

+

Now that the queries are written, the model should be tied to the views +that are going to display the news items to the user. This could be done +in our Pages controller created earlier, but for the sake of clarity, +a new News controller is defined. Create the new controller at +application/controllers/News.php.

+
<?php
+class News extends CI_Controller {
+
+        public function __construct()
+        {
+                parent::__construct();
+                $this->load->model('news_model');
+                $this->load->helper('url_helper');
+        }
+
+        public function index()
+        {
+                $data['news'] = $this->news_model->get_news();
+        }
+
+        public function view($slug = NULL)
+        {
+                $data['news_item'] = $this->news_model->get_news($slug);
+        }
+}
+
+
+

Looking at the code, you may see some similarity with the files we +created earlier. First, the __construct() method: it calls the +constructor of its parent class (CI_Controller) and loads the model, +so it can be used in all other methods in this controller. +It also loads a collection of URL Helper +functions, because we’ll use one of them in a view later.

+

Next, there are two methods to view all news items and one for a specific +news item. You can see that the $slug variable is passed to the model’s +method in the second method. The model is using this slug to identify the +news item to be returned.

+

Now the data is retrieved by the controller through our model, but +nothing is displayed yet. The next thing to do is passing this data to +the views.

+
public function index()
+{
+        $data['news'] = $this->news_model->get_news();
+        $data['title'] = 'News archive';
+
+        $this->load->view('templates/header', $data);
+        $this->load->view('news/index', $data);
+        $this->load->view('templates/footer');
+}
+
+
+

The code above gets all news records from the model and assigns it to a +variable. The value for the title is also assigned to the $data['title'] +element and all data is passed to the views. You now need to create a +view to render the news items. Create application/views/news/index.php +and add the next piece of code.

+
<h2><?php echo $title; ?></h2>
+
+<?php foreach ($news as $news_item): ?>
+
+        <h3><?php echo $news_item['title']; ?></h3>
+        <div class="main">
+                <?php echo $news_item['text']; ?>
+        </div>
+        <p><a href="<?php echo site_url('news/'.$news_item['slug']); ?>">View article</a></p>
+
+<?php endforeach; ?>
+
+
+

Here, each news item is looped and displayed to the user. You can see we +wrote our template in PHP mixed with HTML. If you prefer to use a template +language, you can use CodeIgniter’s Template +Parser class or a third party parser.

+

The news overview page is now done, but a page to display individual +news items is still absent. The model created earlier is made in such +way that it can easily be used for this functionality. You only need to +add some code to the controller and create a new view. Go back to the +News controller and update view() with the following:

+
public function view($slug = NULL)
+{
+        $data['news_item'] = $this->news_model->get_news($slug);
+
+        if (empty($data['news_item']))
+        {
+                show_404();
+        }
+
+        $data['title'] = $data['news_item']['title'];
+
+        $this->load->view('templates/header', $data);
+        $this->load->view('news/view', $data);
+        $this->load->view('templates/footer');
+}
+
+
+

Instead of calling the get_news() method without a parameter, the +$slug variable is passed, so it will return the specific news item. +The only things left to do is create the corresponding view at +application/views/news/view.php. Put the following code in this file.

+
<?php
+echo '<h2>'.$news_item['title'].'</h2>';
+echo $news_item['text'];
+
+
+
+
+

Routing

+

Because of the wildcard routing rule created earlier, you need an extra +route to view the controller that you just made. Modify your routing file +(application/config/routes.php) so it looks as follows. +This makes sure the requests reaches the News controller instead of +going directly to the Pages controller. The first line routes URI’s +with a slug to the view() method in the News controller.

+
$route['news/(:any)'] = 'news/view/$1';
+$route['news'] = 'news';
+$route['(:any)'] = 'pages/view/$1';
+$route['default_controller'] = 'pages/view';
+
+
+

Point your browser to your document root, followed by index.php/news and +watch your news page.

+
+
+ + +
+
+ + + + +
+ +
+

+ © Copyright 2014 - 2017, British Columbia Institute of Technology. + Last updated on Jun 19, 2017. +

+
+ + Built with Sphinx using a theme provided by Read the Docs. + +
+
+
+ +
+ +
+ + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file diff --git a/user_guide/tutorial/static_pages.html b/user_guide/tutorial/static_pages.html new file mode 100644 index 000000000..7449eeea8 --- /dev/null +++ b/user_guide/tutorial/static_pages.html @@ -0,0 +1,634 @@ + + + + + + + + + + Static pages — CodeIgniter 3.1.5 documentation + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ + + + +
+ + + + + + +
+
+
+ +
+
+
+ +
+

Static pages

+

Note: This tutorial assumes you’ve downloaded CodeIgniter and +installed the framework in your +development environment.

+

The first thing you’re going to do is set up a controller to handle +static pages. A controller is simply a class that helps delegate work. +It is the glue of your web application.

+

For example, when a call is made to:

+
+
+

We might imagine that there is a controller named “news”. The method +being called on news would be “latest”. The news method’s job could be to +grab 10 news items, and render them on the page. Very often in MVC, +you’ll see URL patterns that match:

+
+
+

As URL schemes become more complex, this may change. But for now, this +is all we will need to know.

+

Create a file at application/controllers/Pages.php with the following +code.

+
<?php
+class Pages extends CI_Controller {
+
+        public function view($page = 'home')
+        {
+        }
+}
+
+
+

You have created a class named Pages, with a view method that accepts +one argument named $page. The Pages class is extending the +CI_Controller class. This means that the new pages class can access the +methods and variables defined in the CI_Controller class +(system/core/Controller.php).

+

The controller is what will become the center of every request to +your web application. In very technical CodeIgniter discussions, it may +be referred to as the super object. Like any php class, you refer to +it within your controllers as $this. Referring to $this is how +you will load libraries, views, and generally command the framework.

+

Now you’ve created your first method, it’s time to make some basic page +templates. We will be creating two “views” (page templates) that act as +our page footer and header.

+

Create the header at application/views/templates/header.php and add +the following code:

+
<html>
+        <head>
+                <title>CodeIgniter Tutorial</title>
+        </head>
+        <body>
+
+                <h1><?php echo $title; ?></h1>
+
+
+

The header contains the basic HTML code that you’ll want to display +before loading the main view, together with a heading. It will also +output the $title variable, which we’ll define later in the controller. +Now, create a footer at application/views/templates/footer.php that +includes the following code:

+
                <em>&copy; 2015</em>
+        </body>
+</html>
+
+
+
+

Adding logic to the controller

+

Earlier you set up a controller with a view() method. The method +accepts one parameter, which is the name of the page to be loaded. The +static page templates will be located in the application/views/pages/ +directory.

+

In that directory, create two files named home.php and about.php. +Within those files, type some text − anything you’d like − and save them. +If you like to be particularly un-original, try “Hello World!”.

+

In order to load those pages, you’ll have to check whether the requested +page actually exists:

+
public function view($page = 'home')
+{
+        if ( ! file_exists(APPPATH.'views/pages/'.$page.'.php'))
+        {
+                // Whoops, we don't have a page for that!
+                show_404();
+        }
+
+        $data['title'] = ucfirst($page); // Capitalize the first letter
+
+        $this->load->view('templates/header', $data);
+        $this->load->view('pages/'.$page, $data);
+        $this->load->view('templates/footer', $data);
+}
+
+
+

Now, when the page does exist, it is loaded, including the header and +footer, and displayed to the user. If the page doesn’t exist, a “404 +Page not found” error is shown.

+

The first line in this method checks whether the page actually exists. +PHP’s native file_exists() function is used to check whether the file +is where it’s expected to be. show_404() is a built-in CodeIgniter +function that renders the default error page.

+

In the header template, the $title variable was used to customize the +page title. The value of title is defined in this method, but instead of +assigning the value to a variable, it is assigned to the title element +in the $data array.

+

The last thing that has to be done is loading the views in the order +they should be displayed. The second parameter in the view() method is +used to pass values to the view. Each value in the $data array is +assigned to a variable with the name of its key. So the value of +$data['title'] in the controller is equivalent to $title in the +view.

+
+
+

Routing

+

The controller is now functioning! Point your browser to +[your-site-url]index.php/pages/view to see your page. When you visit +index.php/pages/view/about you’ll see the about page, again including +the header and footer.

+

Using custom routing rules, you have the power to map any URI to any +controller and method, and break free from the normal convention: +http://example.com/[controller-class]/[controller-method]/[arguments]

+

Let’s do that. Open the routing file located at +application/config/routes.php and add the following two lines. +Remove all other code that sets any element in the $route array.

+
$route['default_controller'] = 'pages/view';
+$route['(:any)'] = 'pages/view/$1';
+
+
+

CodeIgniter reads its routing rules from top to bottom and routes the +request to the first matching rule. Each rule is a regular expression +(left-side) mapped to a controller and method name separated by slashes +(right-side). When a request comes in, CodeIgniter looks for the first +match, and calls the appropriate controller and method, possibly with +arguments.

+

More information about routing can be found in the URI Routing +documentation.

+

Here, the second rule in the $routes array matches any request +using the wildcard string (:any). and passes the parameter to the +view() method of the Pages class.

+

Now visit index.php/about. Did it get routed correctly to the view() +method in the pages controller? Awesome!

+
+
+ + +
+
+ + + + +
+ +
+

+ © Copyright 2014 - 2017, British Columbia Institute of Technology. + Last updated on Jun 19, 2017. +

+
+ + Built with Sphinx using a theme provided by Read the Docs. + +
+
+
+ +
+ +
+ + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file -- cgit v1.2.3-24-g4f1b