Inheritance in Object-Oriented Programming

Inheritance is one of the core principles of Object-Oriented Programming (OOP). It allows a class (child class) to inherit properties and behaviors (methods) from another class (parent class). This promotes code reusability and establishes a natural relationship between objects.

Why Is Inheritance Important?

• Code Reusability: Eliminates redundant code by allowing child classes to reuse parent class logic.
• Hierarchy and Organization: Helps structure related classes efficiently.
• Extensibility: Enables adding new functionalities without modifying existing code.

How Inheritance Works

In C#, we use the : symbol to define inheritance.

Example:

// Parent class
class BankAccount
{
    protected double balance;
    protected string owner;

    public BankAccount(string owner, double initialBalance)
    {
        this.owner = owner;
        balance = initialBalance > 0 ? initialBalance : 0;
    }

    public void Deposit(double amount)
    {
        if (amount > 0)
        {
            balance += amount;
            Console.WriteLine($"{owner} deposited: {amount}");
        }
    }

    public double GetBalance()
    {
        return balance;
    }
}

// Child class inheriting from BankAccount
class SavingsAccount : BankAccount
{
    private double interestRate;

    public SavingsAccount(string owner, double initialBalance, double interestRate)
        : base(owner, initialBalance)
    {
        this.interestRate = interestRate;
    }

    public void ApplyInterest()
    {
        balance += balance * interestRate;
        Console.WriteLine($"Interest applied to {owner}'s account.");
    }
}

// Using inheritance
var savings = new SavingsAccount("John Doe", 1000, 0.05);
savings.Deposit(500);
savings.ApplyInterest();
Console.WriteLine($"{savings.GetBalance()}");

Key Takeaways:

• SavingsAccount inherits from BankAccount, reusing its methods.
• SavingsAccount extends functionality by adding an interest rate feature.
• The base keyword allows calling the parent class constructor.

Conclusion

Inheritance simplifies code maintenance, promotes reusability, and helps in designing flexible systems. It is a powerful feature that establishes relationships between classes and enables effective hierarchy management.

In the next articles, we will explore more Object-Oriented Programming principles such as Interfaces and Polymorphism, continuing with our structured examples.