FunctionInheritanceTutorial2 created by kenanhancer - https://repl.it/@kenanhancer/FunctionInheritanceTutorial2

FunctionInheritanceTutorial2.js

Function.prototype.inherits = function(parentClassOrObject) {
	let child = this;
	function temp() {
		this.constructor = child;
	}
	temp.prototype = parentClassOrObject.prototype;
	this.prototype = new temp();

	return this;
};

let Person = (function() {
	function Person(personId, firstName, lastName, age, gender) {
		this.personId = personId;
		this.firstName = firstName;
		this.lastName = lastName;
		this.age = age;
		this.gender = gender;
		this.created = Date.now();
		this.updated = Date.now();
		this.isDeleted = false;
	}

	Person.prototype.getFullName = function() {
		return `${this.firstName} ${this.lastName}`;
	};

	Person.prototype.greet = function() {
		return `Hello ${this.getFullName()}`;
	};

	return Person;
})();

let Employee = (function() {
	Employee.inherits(Person);

	function Employee() {
		let args = Array.prototype.slice.call(arguments);

		let _title = args[5];
		let _salary = args[6];

		if (_title) {
			this.title = _title;
		}

		if (_salary) {
			this.salary = _salary;
		}

		this.taxRate = 0.14;

		Person.apply(this, args);
	}

	Employee.prototype.calculateGrossSalary = function() {
		let netSalary = this.calculateNetSalary();

		return netSalary * (1 + this.taxRate);
	};

	Employee.prototype.calculateNetSalary = function() {
		return this.salary * 12;
	};

	return Employee;
})();

let Manager = (function() {
	Manager.inherits(Employee);

	function Manager() {
		let args = Array.prototype.slice.call(arguments);

		Employee.apply(this, args);

		this.taxRate = 0.21;
	}

	Manager.prototype.greet = function() {
		let _greet = Employee.prototype.greet.call(this);
		return `${_greet}, Welcome!`;
	};

	return Manager;
})();

let employee1 = new Employee(1, 'Kenan', 'Hancer', 33, 'MALE', 'WORKER', 1000);

let manager1 = new Manager(2, 'Enes', 'Demir', 40, 'MALE', 'MANAGER', 5000);

console.log(employee1);

console.log(employee1.getFullName());

console.log(employee1.greet());

console.log(employee1.calculateNetSalary());

console.log(employee1.calculateGrossSalary());

console.log();

console.log(manager1);

console.log(manager1.getFullName());

console.log(manager1.greet());

console.log(manager1.calculateNetSalary());

console.log(manager1.calculateGrossSalary());