Introduction To Code Igniter

Introduction To Introduction To CodeIgniterCodeIgniter

Mohammad Amzad HossainSoftwork Solutionstohi1000@yahoo.com

PrerequisitePrerequisite

OOP – Object Oriented Programming

PHPMySQL

IndexIndex Introduction

Evolution Of Web Development Basic Idea Of Web Framework Why Framework not Scratch? MVC ( Model View Controller) Architecture What is CodeIgniter ????

Installation of CodeIgniter Application Flow of CodeIgniter

CodeIgniter URL Controllers Views Models CodeIgniter Libraries Helpers

A Basic Application Development Of Codeigniter Application Flow

Q/A Reference

Evolution of Web Evolution of Web DevelopmentDevelopment

How you first started building How you first started building websites.websites.

Evolution of Web Evolution of Web DevelopmentDevelopment

How you’re building websites How you’re building websites now.now.

Evolution of Web Evolution of Web DevelopmentDevelopment

How you build websites with a How you build websites with a frameworkframework

Basic Idea Of Web Basic Idea Of Web FrameworkFrameworkA web application framework

Is a Software framework Designed to support the development of

Dynamic websites Web applications Web services

Aims to alleviate the overhead associated with common activities used in Web development.

Libraries for database access Templating frameworks Session management Often promote code reuse Many more …….

Why Framework Not Why Framework Not Scratch ? Scratch ? Key Factors of a Development

◦ Interface Design

◦ Business Logic

◦ Database Manipulation

◦ User Access Control

Advantage of Framework ◦ Templating

◦ Provide Solutions to Common problems

◦ Abstract Levels of functionality

◦ Make Rapid Development Easier

Disadvantage of Scratch Development◦ Make your own Abstract Layer

◦ Solve Common Problems Yourself

◦ The more Typing Speed the more faster

MVC ArchitectureMVC Architecture Separates User Interface From Business Logic Model - Encapsulates core application data and functionality

Business Logic. View - obtains data from the model and presents it to the user. Controller - receives and translates input to requests on the model

or the view

Figure : 01

What is CodeIgniter ???What is CodeIgniter ??? An Open Source Web Application Framework Nearly Zero Configuration MVC ( Model View Controller ) Architecture Multiple DB (Database) support DB Objects Templating Caching Modules Validation Rich Sets of Libraries for Commonly Needed Tasks Has a Clear, Thorough documentation

Installation of CodeIgniterInstallation of CodeIgniter Requirments

Web Server - Download & Install Apache PHP – 4.3.2 or Higher Database – MySQL ( support for other DB exists )

Installation Download the latest version from www.codeigniter.com and unzip into

your web root directory. Open “application/config/config.php” and change base_url value to base

url. For example: http://localhost/myci/ To Use Database open “application/config/database.php” and change

necessary values. Usually you have to change: ‘hostname’, ‘username’, ‘password’, ‘datbase’.

Start Your Web Server and Database Server and go to http://localhot/myci

Application Flow Of Application Flow Of CodeIgniterCodeIgniter

Figure : 2 [ Application Flow of CodeIgniter]

CodeIgniter URLCodeIgniter URLURL in CodeIgniter is Segment Based.

www.your-site.com/news/article/my_article

Segments in a URI

www.your-site.com/class/function/ID

CodeIgniter Optionally Supports Query String URL

www.your-site.com/index.php?c=news&m=article&ID=345

ControllersControllersA Class file resides under “application/controllers”

www.your-site.com/index.php/first

<?php

class First extends Controller{

function First() {parent::Controller();

}

function index() {echo “<h1> Hello CUET !! </h1> “;

}}

?>

// Output Will be “Hello CUET!!”

• Note:• Class names must start with an Uppercase Letter.• In case of “constructor” you must use “parent::Controller();”

ControllersControllersIn This Particular Code

<?php

class First extends Controller{

function index() {echo “<h1> Hello CUET !! </h1> “;

}

function bdosdn( $location ) {echo “<h2> Hello $location !! </h2>”;

}}

?>// Output Will be “Hello world !!”

www.your-site.com/index.php/first/bdosdn/world

• Note:• The ‘Index’ Function always loads by default. Unless there is a second segment in the URL

VIEWSVIEWS A Webpage or A page Fragment Should be placed under “application/views” Never Called Directly

<html><title> My First CodeIgniter Project</title><body> <h1> Welcome ALL … To My .. ::: First Project ::: . . . </h1></body></html>

web_root/myci/system/application/views/myview.php

16

VIEWSVIEWSCalling a VIEW from Controller

$this->load->view(‘myview’);

Data Passing to a VIEW from Controller

function index() {$var = array(

‘full_name’ => ‘Amzad Hossain’,‘email’ => ‘tohi1000@yahoo.com’

);$this->load->view(‘myview’, $var);

}

<html><title> ..::Personal Info::.. </title><body>Full Name : <?php echo $full_name;?> <br />E-mail : <?=email;?> <br /></body></html>

VIEWSVIEWSThere are 3 mechanism that can be utilize to show Dynamic Data

inside a VIEW File

- Pure PHP

- PHP’s Alternative Syntax

- CodeIgniter’s Template Engine

<!-- PHP’s Alternative Syntax -->

<?php if( $for_this == true ):?><h1> For This </h1>

<?php elseif( $for_that == true ): ?><h1> For That </h1>

<?php else: ?><h1> What </h1>

<?php endif; ?>

• Note:• There are other alternative syntax ‘for’, ‘foreach’, ‘while’

ModelsModelsDesigned to work with Information of Database

Models Should be placed Under “application/models/”

<?php

class Mymodel extend Model{function Mymodel() {

parent::Model();}function get_info() {

$query = $this->db->get(‘name’, 10); /*Using ActiveRecord*/return $query->result();

}}?>

Loading a Model inside a Controller

$this->load->model(‘mymodel’);$data = $this->mymodel->get_info();

CodeIgniter LibrariesCodeIgniter Libraries

Benchmarking Database Encryption Calendaring

FTP Table File Uploading Email

Image Manipulation Pagination Input and Security HTML

Trackback Parser Session Template

Unit Testing User Agent URI Validation

Special Purpose Classes

$this->load->library(‘database’);

Loading CodeIgniter Library

CodeIgniter LibrariesCodeIgniter LibrariesDatabase LibraryAbstract Database Class support traditional structures and Active Record Pattern.

function index() {

$this->load->library(‘database’);$rslt = $this->db->query(“select first_name from user_name”);foreach( $rslt->result() as $row_data)

echo $row_data->first_name . “<br />”;

}

function index() {

$this->load->library(‘database’);$this->db->select(“first_name”);$rslt = $this->db->get(“user_name”);foreach( $rslt->result() as $row_data)

echo $row_data->first_name . “<br />”;

}

Active Record Pattern

General Approach

HelpersHelpersSimply a collection of functions in a particular category.

Array Date File HTML Smiley Text

URL Cookie Download Form Security String

Directory E-mail Inflector XML Parser Typography

$this->load->helper(‘helper_name’);

Loading A Helper Inside a Controller

$this->load->helper(array(‘form’,’url’) );

HelpersHelpersForm Helper

form_open() form_open_multipart() form_input() form_textarea() form_checkbox() form_submit() form_close()

URL Helper site_url() base_url() anchor() anchor_popup() mailto()

A Personal Blog Using CIA Personal Blog Using CI

Questions & Questions & AnswersAnswers

Useful Links www.codeigniter.com http://codeigniter.com/wiki/Summary_of_Resources_Li

braries_Helpers_Plugins.../

ReferenceReference User Guide of CodeIgniter 1.6.1 Wikipedia PHPit Slideshare