object orient programming with php

here we will start with basic class of object orient programming in php.

Class , properties , methods , instance :

<?php 

class Fruit{

    //class properties 
    public $name ; //property-1
    public $color ; //property-2

     // Methods

    // method-1 this is a setter method 
    // we will assign a value in public $name property using
    // this set_name() setter method
    public function set_name($name){ 
        $this->name = $name ; //about $this keyword 
        // $this keyword is targeting parent scope of set_name()
        // method or Current Objects property public $name
        // and equal sign is assigning 
        // value of $name parameter 
        // to targeted public $name property
    }

    //method-2 this is a getter method 
    //we will get or retrive the value of public $name property
    // using this get_name() getter method
    function get_name() {
        return $this->name;
    }

}

$f1 = new Fruit(); //creating instance of Fruite Class named $f1
//now $f1 get all access of properties and methods of Fruite
//Class

$f1->set_name('sakura plum'); // setting public $name property 
//value using set_name setter method and value is "sakura plum"

echo($f1->name); //here we accessing the value of public $name 
//property using instance named $f1 of Fruite Class
// note we can access directly public $name value if property 
//is public if property is private like private $name then we 
//must need a getter_method to access the value 
//of private $name property

echo( $f1->get_name()); // here we are getting property value
//of $public name using get_name() getter method 


//here is example for more then one property value assign 
//using one setter method is same Fruite class


class Fruit{

    //class properties 
    public $name ; 
    public $color ; 

    //methods
    function set_name($name , $color)
    {
        $this->name = $name; //setting name 
        $this->color = $color ; //setting color 
    }
    function get_name()
    {
        //getting values of name and color 
        return "The Name Is :".$this->name. " And The Color Is : ".$this->color;
    }

}
$f1 = new Fruit(); //instance 1 for Fruite Class $f1 have all
//properties and methods that Fruite Class have

//we don't need to write Fruite Class properties and methods 
//again we can reuse Fruite Class as needed 
//this is the super power of Object orient programming 

$f2 = new Fruit(); //instance 2 for Fruite Class $f2 have all
//properties and methods that Fruite Class have

$f1->set_name('sakura plum','indigo'); 
//$f1 blue print for Fruite
echo( $f1->get_name()); 

$f2->set_name('blue berry','navy blue'); 
//same named classes blue print for $f2 
echo($f2->get_name());

echo($f2 instanceof Fruit); //this line will return 1 
// instence of will check if $f2
//is instance or not of Fruite Class 

echo($f2 instanceof Fruitt); //this line will return nothing

?>

__construct and __destruct methods oop in php:

class Fruit
{
    public $name;
    public $color;
    //__construct() method is allow us to initialize an 
    //object's properties when we create the instance of 
    //class with out write setter_method
    //__contruct method starts with two under score
    function __construct($name, $color)
    {
        $this->name = $name ; 
        $this->color = $color ; 
    }
    // __distruct method  if we create a distruct method
    // php will call it 
    // automatically at the end of the script 
    function __destruct(){
        echo "The Fruit Name is {$this->name} and the fruit color is {$this->color}";
    }
}

$f1 = new Fruit('sakura plum','indigo');
$f2 = new Fruit('blue berry','navy blue');

//we don't need to echo to view the properties current value

access modifiers in php:

public - the property or method can be accessed from everywhere. This is default
protected - the property or method can be accessed within the class and by classes derived from that class
private - the property or method can ONLY be accessed within the class

<?php

class Fruit
{
    public $name ; 
    protected $color ; 
    private $weight ; 

    public function set_name($name){
        $this->name = $name ; 
    }
    public function set_color($color){
        $this->color = $color ; 
    }
    public function set_weight($weight){
        $this->weight = $weight ; 
    }
    public function get_color(){
        return $this->color ; 
    }
    public function get_weight(){
        return $this->weight ; 
    }
}

$mango = new Fruit() ; 

$mango->name = "mm"; //will not give a error 
//but 
//$mango->color = "col"
// $mango->weight = 1010 
// will throw a error because color is protected and 
// weight is private property to set a value in 
// color and weight we need a setter method 
// and when we want to access the value of 
// color and weight , we need e getter method

$mango->set_name('mango');
$mango->set_color('green');
$mango->set_weight('1010');

echo($mango->name); // name can be access because its public 
echo($mango->get_color());
echo($mango->get_weight());

?>

php-basics-revision [topic-name: Class/object,constructor,destructor,access modifiers]