Polymorphism

Definition :

Polymorphism is an object-oriented programming concept that means "many forms." It allows the same method name to behave differently based on the object that is calling it. There are two main types:

• Compile-time polymorphism (Method Overloading) – supported in C# and Java.
• Run-time polymorphism (Method Overriding) – supported in C#, Java, Python, and JavaScript.

This concept improves flexibility and code reusability.

---

C++

Syntax

class BaseClass {
public:
    virtual void methodName() {
        // base class behavior
    }
};

class DerivedClass : public BaseClass {
public:
    void methodName() override {
        // overridden behavior
    }
};

Example

#include <iostream>
using namespace std;

class Person {
public:
    virtual void displayInfo() {
        cout << "Person: General Info" << endl;
    }
};

class Student : public Person {
public:
    void displayInfo() override {
        cout << "Student: Specific Info" << endl;
    }
};

int main() {
    Person* p = new Student();
    p->displayInfo();  // Output: Student: Specific Info
    delete p;
    return 0;
}

---

C#

Syntax

class className {
    public virtual void methodName() {
        // base class behavior
    }
}

class DerivedClass : className {
    public override void methodName() {
        // overridden behavior
    }
}

Example

using System;

class Person {
    public virtual void displayInfo() {
        Console.WriteLine("Person: General Info");
    }
}

class Student : Person {
    public override void displayInfo() {
        Console.WriteLine("Student: Specific Info");
    }
}

class Program {
    static void Main() {
        Person p = new Student();
        p.displayInfo();  // Output: Student: Specific Info
    }
}

---

Java

Syntax

class className {
    public void methodName() {
        // base class behavior
    }
}

class DerivedClass extends className {
    @Override
    public void methodName() {
        // overridden behavior
    }
}

Example

class Person {
    public void displayInfo() {
        System.out.println("Person: General Info");
    }
}

class Student extends Person {
    @Override
    public void displayInfo() {
        System.out.println("Student: Specific Info");
    }

    public static void main(String[] args) {
        Person p = new Student();
        p.displayInfo();  // Output: Student: Specific Info
    }
}

---

Python

Syntax

class className:
    def methodName(self):
        # base class behavior
        pass

class DerivedClass(className):
    def methodName(self):
        # overridden behavior
        pass

Example

class Person:
    def display_info(self):
        print("Person: General Info")

class Student(Person):
    def display_info(self):
        print("Student: Specific Info")

p = Student()
p.display_info()  # Output: Student: Specific Info

---

JavaScript

Syntax

class className {
    methodName() {
        // base class behavior
    }
}

class DerivedClass extends className {
    methodName() {
        // overridden behavior
    }
}

Example

class Person {
    displayInfo() {
        console.log("Person: General Info");
    }
}

class Student extends Person {
    displayInfo() {
        console.log("Student: Specific Info");
    }
}

const p = new Student();
p.displayInfo();  // Output: Student: Specific Info

---

TypeScript

Syntax

class BaseClass {
    methodName(): void {
        // base class behavior
    }
}

class DerivedClass extends BaseClass {
    override methodName(): void {
        // overridden behavior
    }
}

Example

class Person {
    displayInfo(): void {
        console.log("Person: General Info");
    }
}

class Student extends Person {
    override displayInfo(): void {
        console.log("Student: Specific Info");
    }
}

const p: Person = new Student();
p.displayInfo();  // Output: Student: Specific Info

---

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