Reflection-In-PHP

Reflection in PHP

Presenter: Deepak Rai, Mindfire SolutionsDate: 30/06/2014

Presenter: Deepak Rai, Mindfire Solutions

About me:

Skills: PHP, MySQL, JavaScript, jQuery, HTML, CSS CodeIgniter, StoredProcedures, SVN, GIT.

Certifications:– Oracle Certified Professional (OCP) MySQL– Oracle Certified Associate (OCA) MySQL– Microsoft Certified HTML5, CSS3 and Javascript programmer

Contact me: Skype: mfsi_deepakr E-mail: [email protected]

Facebook: www.facebook.com/deepakrai89 LinkedIn: https://www.linkedin.com/in/deepakrai89 Google Plus: https://plus.google.com/114288591774549019180/ Twitter: www.twitter.com/__deepakrai


Agenda

– Introduction to PHP Reflection API– How to use it from command line– Different classes available in API– How to get more information about a Class or a Method using this API– Examples of creating HTML Forms and Database tables– Different PHP well known frameworks using this API– Benefits of using Reflection API

What is Reflection in Programming Languages ?

Reflection is generally defined as a program's ability to inspect itself and modify its logic at execution time. In less technical terms, reflection is asking an object to tell you about its properties and methods, and altering those members.


Using Reflection API from command line

$ php --rf strlen

Function [ <internal:Core> function strlen ] {

- Parameters [1] {

Parameter #0 [ <required> $str ]

}

}

$ php --rf array_merge

Function [ <internal:standard> function array_merge ] {

- Parameters [3] {

Parameter #0 [ <required> $arr1 ]

Parameter #1 [ <required> $arr2 ]

Parameter #2 [ <optional> $... ]

}

}


Classes available in PHP Reflection API

Class Name Description

ReflectionClass Gives information about a class

ReflectionFunction Reports information about a function

ReflectionMethod Reports information about a method

ReflectionParameter Retrives information about method's or function's parameter

ReflectionProperty Gives information about a properties

ReflectionObject Gives information about an object


Few more classes are available in Reflection API apart from above mentioned.

Methods available in PHP “ReflectionClass” Class

Method Name Description

getProperties Gets all properites of the class

getMethods Gets all methods of the class

getDocComment Get Class Document comment

getFileName Gets the file name of the file in which the class has been defined

getParentClass Gets parent class

hasMethod Checks if method is defined

Presenter: Deepak Rai, Mindfire SolutionsReflectionClass has a long list of methods.

Using 'ReflectionClass' class to get class information

<?php

class myClass{

public $var;

. . .

public function myFun(){

. . .

}

}

$myClassObj = new myClass();

$myClassRef = new ReflectionClass($myClassObj);

print_r($myClassRef);

print_r($myClassRef->getProperties());

print_r($myClassRef->getMethods());

ReflectionClass Object

(

[name] => myClass

)

Array

(

[0] => ReflectionProperty Object

(

[name] => var

[class] => myClass

)

)

Array

(

[0] => ReflectionMethod Object

(

[name] => myFun

[class] => myClass

)

)


Using 'ReflectionMethod' class to get a method information

class sumClass{ /**

* @access public

* @var $a

* @var $b

*/

public function setNum($a, $b = 5){

. . .

. . .

}

}

$sumObj = new sumClass();

$setNumMethodReflection = new ReflectionMethod($sumObj, 'setNum');

print_r($setNumMethodReflection);

echo $setNumMethodReflection;

/**

* @access public

* @var $a

* @var $b

*/

Method [ <user> public method setNum ] {

@@ /home/deepak/Desktop/ReflectionPHP/ReflectionMethodExample.php 25 - 31

- Parameters [2] {

Parameter #0 [ <required> $a ]

Parameter #1 [ <optional> $b = 5 ]

}

}


Applicationsof PHP Reflection

API


Generating HTML form from a PHP classIn Models, generally a Model class represents a DB table for which data is taken by

HTML formclass Person {

private $first_name;

private $last_name;

private $age;

private $email;

/**

* Set first name

*/

public function set_first_name($first_name){

$this->first_name = $first_name;

}

/**

* Set last name

*/

public function set_last_name($last_name){

$this->last_name = $last_name;

}

/**

* Set age

*/

public function set_age($age){

$this->age = $age;

}

/**

* Set email

*/

public function set_email($email){

$this->email = $email;

}

}


Generating HTML form from a PHP classIn Models, generally a Model class represents a DB table for which data is

taken by HTML form (continued..)

// include the class

require_once 'Person.php';

$person_reflection = new ReflectionClass('Person');

// get all methods of Class 'Person'

$person_methods = $person_reflection->getMethods();

// output html form

create_html_form($person_methods);

function create_html_form($person_methods){

/* loop through each method and create html element for each setter method */

foreach($person_methods as $method){

$method_name = $method->getName();

/* if method name prefix is 'set_' the create form element */

if(strpos($method_name, 'set_') !== FALSE){

echo '<label for="'.substr($method_name,4).'">'

.str_replace('_',' ',substr($method_name,4))

.'</label>';echo "<br/>";

echo '<input type="text" name="'.substr($method_name,4).'" />';

echo "<br/>";

}

}

}Presenter: Deepak Rai, Mindfire Solutions

Creating DB Table from PHP Class<?php

/**

* @table="task"

*/

class Task

{

/**

* @Column(type="int", strategy="auto")

*/

protected $id;

/**

* @Column(type="text")

*/

protected $taskDescription;

/**

* @Column(type="date")

*/

protected $dueDate;

}

We can create Database tables using PHP reflection API.

We can read Class and Properties Doc comments to filter it out to extract the useful information like table name

So, here table name is task. Columns are id, taskDescription and dueDate


PHP Class Documentation Tool


We can use PHP Reflection API to generate documentation of any PHP class.

DEMO

PHP Frameworks using PHP API

- PHPUnit Framework.- Code Analysis frameworks (RIPS, a source code analyser).- CakePHP (AclExtra library uses Reflection API to find all controllers

and methods).- Laravel uses Reflection API for dependency injection.- Doctrine ORM uses Reflection API for working with the entities.


Benefits of using Reflection

- Duck typing is not possible with Reflection API.- HTML Form Generation.- Creating DB Tables.- Creating Documentation of poorly documented 3rd party classes.- Accessing private properties and methods.



?


Thank you

www.mindfiresolutions.com

https://www.facebook.com/MindfireSolutions

http://www.linkedin.com/company/mindfire-solutions

http://twitter.com/mindfires

PHP Manual - http://php.net/manual/en/intro.reflection.php

TutsPlus - http://code.tutsplus.com/tutorials/reflection-in-php--net-31408

References:

Reflection-In-PHP

Software

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