What is object in PHP. Objects are actual-world like entities. Objects are determined from classes in Object-Oriented Programming like PHP. When a class is specified, we can build various objects out of the class. Example Class Colors is described, then Blue, White, Green are all objects of the Class Color. A class is a blueprint of an object. A class holds variables and functions. These data variables are declared properties and data functions are called data methods.
The meaning of an object performs like this, An object is an instance of a class. We can build an instance of the class by using the new keyword. We can create multiple instances of the class. These cases can now access the class functions, the class members.
How to Create an Object in php?
Building an object is the same as instantiating a class. This case is created using the new keyword. This process is called initialization. Since objects are instances of a class and can be performed using a new keyword let us take a look at how these instances are created.
//Syntax objectname = new Classname(); // Php object Example. $elephant= new Animal(); $KomodoDragon = new Animal(); $Emu = new Animal()
Above are three different objects of the class Animal. Using these objects we can obtain the properties and functions of class Animal.
Properties of Object in php
Properties are variables that are enclosed within a class. These variables are used by the rules/method, objects of the class. These variables can be public, private, protected. By default, the public is used. The value of a variable may or may not hold a default value, meaning that the variable may be initialized with a value or not.
The variable names are case sensitive, meaning that $var is different from $Var. There is a naming protocol like if the variable contains more than one word then the second word will start with a capital letter like $varname, $var2nameand so on.
Let us look at the below program to understand the properties.
class Dog {
public $dogrun = 'Land';
public $dogSound = 'Bark';
public $
birdsBuildNests ='trees';
}The below program explains how to represent a class Dog and its properties like a dog runs make sound and build faith and a method on what a dog does.
<?php
class Dog {
public $dogRuns = 'Land';
public $dogSound = 'Bark';
public $dogBuild = 'Faith';
//methods
public function dogDoes()
{
echo 'Dog';
}}
$obj = new Dog();
echo '<br> Dog Runs = '.$obj->DogRuns;
echo '<br> Dog Makes Sound = '.$obj->DogSound;
echo '<br> Dog Build = '.$obj->DogBuild;
?>Methods of Object in PHP
As the properties of a class, we can determine member functions in a class. These functions can be called from an object and methods of a class. These functions can be public, private, or protected. By default is public. Also while declaring the function we declare it as
//syntax
public function nameofafunction() {
//statements
}Example:
<?php
class Birds {
public $dogrun;
public $dogbuild;
public function set_dogRuns($input) {
$this->dogrun = $input ;
}
// Method1
public function get_dogRuns() {
return $this->dogrun;
}
// Method2
public function set_DogBuild($input) {
$this->dogbuild = $input ;
}
//Method2
public function get_DogBuild() {
return $this->dogbuild;
}
}
$obj = new Birds();
$obj->set_dogRuns('Land');
echo '<br> Dog Flies = '.$obj->get_dogRuns();
$obj->set_DogBuild('Trees');
echo '<br> Dog Builds = '.$obj->get_DogBuild();?>Object and Constructors
A constructor is a specific method. When a new object is created this method is requested automatically. There is no requirement for calling the method explicitly from an object.
_construct(); // double underscores are used.
Suppose there are two classes one parent class and the other is child class. If the child class do not have its own constructor and wants to inherit the parent class constructor we need to declare it in the following syntax:
parent::__construct();
Conclusion
This article describes what is an object in object-oriented programming, how to create an object, its syntax, how to use an object in a given program. Also, how to declare and use properties and methods of an object in PHP, how to use constructors in PHP. This article could be effective to solve your doubts and get the idea well.