Principles of MVC for PHP Developers

Principles of MVC for PHP Developers

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  Principles of MVCFor PHP Developers View PHP & MYSQL Course at: http://www.edureka.co/php-mysql For more details please contact us: US : 1800 275 9730 (toll free) INDIA : +91 88808 62004 Email Us : sales@edureka.co For Queries: Post on Twitter @edurekaIN: #askEdureka Post on Facebook /edurekaIN
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  Slide 2 www.edureka.co/php-mysql Objectives Atthe end of this module, you will be able to understand:  Challenges Faced when Designing an Application Without Framework  MCV Design Patterns  Logic Behind MVC  DRY and Convention Over Configuration  MVC Benefits  Demo on MVC in PHP
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  Slide 3 www.edureka.co/php-mysql ChallengesFaced when Designing an Application without a Framework  Complexity in Coding in straight PHP  Everything must be tested; which is difficult  Difficult to re-use code  Hard code everything from scratch  Teamwork challenges - parallel programming cannot be done efficiently
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  Slide 4 www.edureka.co/php-mysql Leads to disorganization  Change one thing , break another Challenges Faced when Designing an Application without a Framework
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  Slide 5 www.edureka.co/php-mysql TheSolution is to use Design Patterns Design Patterns is the way to organize a program in a proper manner One such design pattern is MVC
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  Slide 6 www.edureka.co/php-mysql Introduction– What is MVC MVC Introduction MVC is acronym for Model-View-Controller A software design pattern for developing web and desktop applications In simple words, a better way of separating the logic of your application from the display.
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  Slide 7 www.edureka.co/php-mysql Originally described in terms of a design pattern for use with Smalltalk by Trygve Reenskaug in 1979.  His paper was published under the title "Applications Programming in Smalltalk-80: How to use Model-View- Controller", and paved the groundwork for most future MVC implementations.  MVC design pattern is used to separate an application’s data, business logic, and presentation; doing so facilitates the creation of more maintainable, reusable, and testable code. • Model - Data Layer • View - User Interface Layer • Controller - Interacts with the Model MVC Introduction
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  Slide 8 www.edureka.co/php-mysql MVC- Illustration Web Browser/Client HTTP Request HTTP Response CONTROLLER MODEL VIEW Data object Request Data Objects Response Render dataEvents (GET/POST) Handled by Framework (Hidden from user) Database Database Request Raw Data Response MVC Container Website User http://www.mywebsite.com
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  Slide 9 www.edureka.co/php-mysql Model Dataaccess routines and some business logic can be defined in the model. Model is responsible for providing the data from the database and saving the data into the data store. Models are active representations of database tables: they can connect to your database, query it (if instructed to do so by a controller) and save data to the database. No interaction between models and views: all the logic is handled by controllers. MVC - Data Layer
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  Slide 10 www.edureka.co/php-mysql View Viewsdefine exactly what is presented to the user. It collects data from the user and gives it to controller and controller invokes the required model. Controllers pass data to each view to render in some format. Views can be described as template files that present their content to the user: variables, arrays and objects that are used in views are registered through a controller. Views should not contain complex business logic; only the elementary control structures necessary to perform particular operations, such as the iteration of collected data through a foreach construct, should be contained within a view. MVC - User Interface Layer
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  Slide 11 www.edureka.co/php-mysql Controller Controllersbind the whole pattern together. Controller is intermediary between View and Model. Controllers contain the logic of your application. Each controller can offer different functionality; controllers retrieve and modify data by accessing database tables through models; and they register variables and objects, which can be used in views. Once request is received from client it executes the appropriate business logic from the model, decide which view to display based on the user's request and other factors, pass along the data that each view will need, or hand off control to another controller entirely. MVC - Interacting With Model
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  Slide 12 www.edureka.co/php-mysql DRY DRY just means "Don't Repeat Yourself". Make sure that when you write code, you only write it one time.  The DRY principle is stated as "Every piece of knowledge must have a single, unambiguous, authoritative representation within a system." Reference: https://maurits.wordpress.com
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  Slide 13 www.edureka.co/php-mysql ConventionOver Configuration  Convention over configuration (also known as coding by convention) is a software design paradigm which seeks to :  For example, if there is a class Sale in the model, the corresponding table in the database is called "sales" by default. It is only if one deviates from this convention, such as calling the table "product sales", that one needs to write code regarding these names. Not losing flexibility Decrease number of decisions on developers Gain Simplicity
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  Slide 14 www.edureka.co/php-mysql MVCBenefits
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  Slide 15 www.edureka.co/php-mysql Demoon MVC in PHP
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  Questions Slide 16 www.edureka.co/php-mysqlTwitter@edurekaIN, Facebook /edurekaIN, use #AskEdureka for Questions