Structure vs Class in C++: Key Differences Explained

Practical Implementation

In C++, structs and classes define custom data types, but they differ in default access specifiers and member functions. Explore practical examples to understand how structures and classes in C++ contrast with each other.

Structure Example

A structure is a user-defined data type that can hold multiple data members of different data types. By default, all members of a structure are public.

struct Person {
    std::string name;
    int age;
    void displayInfo() {
        std::cout << "Name: " << name << ", Age: " << age << std::endl;
    }
};

int main() {
    Person person1;
    person1.name = "Alice";
    person1.age = 30;
    person1.displayInfo();
    return 0;
}
    

Class Example

A class is similar to a structure but has additional features like data hiding and member functions. By default, all members of a class are private.

class Car {
private:
    std::string brand;
    int year;
public:
    Car(std::string b, int y) : brand(b), year(y) {}

    void displayInfo() {
        std::cout << "Brand: " << brand << ", Year: " << year << std::endl;
    }
};

int main() {
    Car car1("Toyota", 2021);
    car1.displayInfo();
    return 0;
}
    

Step-by-Step Implementation Guide

• Define a structure using the struct keyword for simple data containers.
• Define a class using the class keyword for more complex data types with member functions.
• Access members of a structure directly since they are public by default.
• Use member functions to access and manipulate data members of a class.

Best Practices and Optimization Tips

• Use structures for simple data containers without member functions.
• Use classes for more complex data types that require data encapsulation and abstraction.
• Avoid exposing class members directly; prefer encapsulation through private data members and public member functions.

Common Pitfalls and Solutions

One common pitfall is forgetting to specify access specifiers in classes, leading to unexpected member visibility. Always explicitly define the access specifiers (public, private, protected) in classes to maintain code clarity and prevent unintended access.