Defining a class and creating an object php
In PHP programming, a class data type is a user-defined custom data type, similar to a blueprint structure collection, that helps PHP programmers define custom class data types and class object parameters, enabling them to define class properties and class methods (functions) in a user-defined custom class. A class object in PHP is an example of a user-defined variable that holds the actual values and parameters associated with class properties in the current program, and invokes functions and methods defined in the current class.
So, let’s learn how to define a class in PHP programming and create a class object.
Defining a Class in PHP Programming.
In PHP programming, a class data type is declared with the class keyword and defined with the class name, class data type, parameters, and function. In a typical PHP program class, programmers can define class properties and class methods (functions).
Example of defining a class in PHP programming.
<?php
//here we create a user define class
class employee {
// set properties attributes for class
public $emp_name;
public $emp_id;
public $salary;
// here we create a Constructor method that called when an object is created
public function __construct($emp_name, $emp_id, $salary) {
$this->emp_name = $emp_name;
$this->emp_id = $emp_id;
$this->salary = $salary;
}
// here we define a class Method used in function within the class
public function displayInfo() {
echo “Employee – ” . $this->salary. , $this->emp_name . , $this->emp_id . “<br>”;
}
}
?>
Explanation of user defined class in php.
- Class properties – Here, the $emp_name, $emp_id, and $salary variables in this class display multiple variable properties in the class.
- Class Constructor – The __construct() method in a PHP class initializes class properties when constructing an existing class object.
- Class Method – Here, the displayInfo() class method in the program displays the information of the Employee class object.
Creating an object in PHP programming means instantiating a class.
Once a custom user-defined class is defined in a PHP program, programmers can create multiple object classes (instances) for that class by using the new keyword.
Example of object creation from a class in PHP programming.
<?php
// let Create an object object of the employee class
$employee1 = new employee(“Siddhi”, “101”, 10000);
// Here we are accessing the properties of the class object.
echo $employee1->emp_name . “<br>”; // Result – Siddhi
echo $employee1->emp_id . “<br>”; // Result – 101
echo $employee1->salary . “<br>”; // Result – 10000
// Here we are calling a method of the class object.
$employee1->displayInfo(); // Result – employee Siddhi 101 10000
?>
Explanation of object classes (instances) in PHP programming.
- $employee1 – This is an object element created in the class named Employee using the new keyword.
- Accessing properties – Here the programmer can access the properties of the class object using the -> operator, for example, $employee1->emp_name operator.
- Calling a method – Class is User -> Operator. Which can call the methods defined in the class using the $employee1->displayInfo()) function class method.
Complete class example in PHP programming.
<?php
//here we Define the employee name class
class employee {
public $emp_name;
public $emp_id;
public $salary;
// here we used or create Constructor to initialize the class object properties
public function __construct($emp_name, $emp_id, $salary) {
$this->emp_name = $emp_name;
$this->emp_id = $emp_id;
$this->salary = $salary;
}
// here class Method used to display employee element information
public function employeeInfo() {
echo “Employee Detail – ” . $this->salary. , $this->emp_name . , $this->emp_id . “\n”;
}
}
// here we Create two class objects of the employee class
$employee1 = new employee(“Bhavishi deora”, “E101”, 10000);
$employee2 = new employee(“Harry deora”, “E102”, 11000);
// let we use Accessing properties of employee1 and employee2 class object
echo $employee1->emp_name . , $employee1->emp_id . , $employee1->salary. “]\n”;
echo $employee2->emp_name . , $employee2->emp_id . , $employee2->salary. “]\n”;
// Let employee class methods of employee1 and employee2 be called
$employee1->employeeInfo(); // Result – 10000 Bhavishi deora E101
$employee2->employeeInfo(); // Result – 11000 Harry deora E102
?>
Complete class explanation.
- Here, in the class program, the programmer creates two objects by using the new keyword and passing important arguments to the constructor. For example, $employee1 and $employee2.
- Here, the programmer can access and use the properties and class methods defined in the class according to the conditions given in the current program example.
Summary of Class Properties Object Methods in PHP Programming.
- Class – This defines a user-defined class structure blueprint for class objects.
- Object – This is an instance of a class created by using the new Class keyword in a user-defined class.
- Constructor (__construct) – This is a user-defined special function in an existing class that is automatically called when creating an existing class object.
- Properties – Class properties are variables in the class that store and process data for each user-defined class object.
- Methods – These are functions defined within a user-created class that explain the behavior of an existing class object.
