CodeIgniter framework learning essay, codeigniter essay_PHP tutorial

CodeIgniter framework learning essay, codeigniter essay

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Codeigniter Framework

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Lecturer: Zou Yiliang

Weibo: weibo.com/it266

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Main content

Introduction to CI

An in-depth look at the MVC design pattern

Controllers and views in CI

Super objects in CI

Database access

AR model

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What is CI?

CodeIgniter is a lightweight but powerful PHP framework

Based on the MVC design pattern, it provides a rich set of class libraries

Easy to learn, efficient and practical

Official website

www.codeigniter.com

Chinese website

http://codeigniter.org.cn

Download the latest version

CodeIgniter_2.1.4.zip

(The latest version as of 2015.7.1 is 3.0.0 - author's note)

What are the characteristics?

You want a compact frame

You need great performance

You need broad compatibility with various PHP versions and configurations on standard hosts

CI 2.1.4 requires PHP5.1.6

You want a framework that requires almost 0 configuration

You want a framework that doesn’t require any commands

You want a framework that doesn’t have to adhere to restrictive coding rules

You don’t want to be forced to learn a template language (although you can choose your preferred template parser)

You don’t like complexity, you love simplicity

You need clear, complete documentation

Directory structure description

license.txt License Agreement

user_guide User Manual

syste Framework core file

application application directory

index.php entry file

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MVC

1. Entry file

The only script file that the browser directly requests

2. Controller

Coordinate models and views

3. Model

Provide data and save data

4. View

Only responsible for displaying

Form...

5. Action

is a method in the controller, used to be requested by the browser

MVC in CI

Pathinfo is used to access the url

Entry file.php/controller/action

Application directory:

controllers controllers

models models

views views

The default controller is welcome

The default action is index

Controller

1. No need to add suffix

2. The file name should be all lowercase For example user.php

3. All controllers directly or indirectly inherit from the CI_Controller class

4. In the controller, the action (method) requirements are:

public

Cannot start with _

View

1. If you load the view in the controller

//Write the view name directly without the extension. If there is a subdirectory, write the directory name

2. In the view, use native PHP code directly

3. Recommended to use

                                                                                      

                                

                             

Super Object

Current controller object

provides many attributes:

$this->load

Instance of loader class system/core/loader.php

Methods provided by the loader class:

view() Loading view

vars() Assign variables to the view

database() loads the database operation object

model() Load model object

helper()

$this->uri

Is an instance of the CI_URI class system/core/URI.php

Methods provided by the CI_URI class:

segment() is used to obtain the parameters in the uri

Traditional: Entry file.php/controller/action/parameter1/value1/parameter2/value2

Entry file.php/controller/action/value1/value2

echo $this->segment(3);//value 1

echo $this->segment(4);//value 2

//index.php/controller/index/6

public function index($p=0){ echo $p;//output 6

}

$this->input

Input class

Is an instance of the CI_URI class system/core/input.php

Methods provided by the CI_URI class:

$this->input->post('username'); //Equivalent to $_POST['username'];

$this->input->server('DOCUMENT_ROOT'); //Equivalent to $_SERVER['DOCUMENT_ROOT'];

$this->input->server('REMOTE_ADDR');

In the view, use $this directly to access the properties in the super object

Database access

Modify configuration file

application/config/database.php

Load the database access object into the attribute of the super object $this->db

$this->load->query($sql);//Return object

$res=$this->db->query($sql);//Return object

$res->result();//Returns an array, the array is an object one by one

$res->result_array();//Returns a two-dimensional array, which is an associative array

$res->row()//Return the first piece of data, which is directly an object

Parameter binding

$sql="select * from blog_user where name=?";
$this->db->query($sql,$name);//if When there are multiple question marks, an index array
needs to be passed in
Table prefix

$db['default']['dbprefix'] = 'new_';

$db['default']['swap_pre'] = 'swap_';

The configuration is the same. In the code, just hard-code the table prefix. If the project database table prefix changes in the future,
you only need to modify $db['default']['dbprefix'] = ' new_';swap_ in the code will be automatically replaced with new_

Automatic loading of db
applicationconfigautoload.php
$autoload['libraries'] = array(database);
Not required: $this->load->database();