C++ Classes

Introduction to C++ Classes

C++ classes are a fundamental building block in object-oriented programming. They allow developers to create user-defined types that model real-world entities, encapsulating both data and behavior. In C++, you define a class using the class or struct keyword, although there are some differences in their default access specifiers.

Defining a Class

A class definition in C++ typically includes data members (variables) and member functions (methods). The data members hold the state of the object, while the member functions define the behavior.

Here's a simple example of a C++ class definition:

Using a Class

Once a class is defined, you can create objects of that class and use them in your program. Here is how you can create an object of the Car class and use its member function:

Classes vs. Structs

In C++, both class and struct can be used to define a user-defined type. The primary difference lies in the default access specifiers: members of a class are private by default, while members of a struct are public by default. This difference can affect encapsulation and data hiding.

Here's an example using struct:

Access Specifiers

Access specifiers control the accessibility of class members. The three primary access specifiers in C++ are:

• Public: Members are accessible from outside the class.
• Private: Members cannot be accessed (or viewed) from outside the class.
• Protected: Members cannot be accessed from outside the class, but they can be accessed in derived classes.

Using access specifiers, you can control the interface and encapsulation of your objects, ensuring that only the intended interactions are allowed.

Constructor and Destructor

Constructors and destructors are special member functions in a class. A constructor initializes objects of a class, while a destructor cleans up when an object is no longer in use.

Here's how you can define a constructor and a destructor in a class:

In the above example, the constructor takes parameters to initialize the data members, and the destructor simply prints a message when the object is destroyed.