What are the different ways of defining members of a class? Discuss with example. How Encapsulation is achieved in C++?

 In C++, the members of a class can be defined using different access specifiers such as public, private, and protected. These access specifiers determine the visibility of the members to other classes and functions.

Public members are accessible to all the functions and classes, whereas private members are only accessible to the functions and classes defined within the same class. Protected members are similar to private members, except that they can be accessed by the classes that inherit from the base class.

Example:

class Employee {
public:
   int empID;
   string empName;
private:
   float salary;
   
protected:
   int empAge;
};

Encapsulation in C++ refers to the concept of bundling the data members and member functions within a single unit, i.e., the class. The access specifiers play a significant role in achieving encapsulation by providing the necessary control over the access to the members of the class.

By keeping the data members private and providing public member functions to access and modify the data, the class can prevent unauthorized access and ensure data integrity. This also provides better maintainability and flexibility to the code, as any changes made to the implementation details of the class do not affect the code that uses the class interface.

Example:

class BankAccount {
private:
   int accountNo;
   string holderName;
   float balance;
public:
   void deposit(float amount) {
      balance += amount;
   }
   
   void withdraw(float amount) {
      if (balance >= amount) {
         balance -= amount;
      } else {
         cout << "Insufficient balance!";
      }
   }
   
   float getBalance() {
      return balance;
   }
};

In this example, the class BankAccount encapsulates the data members accountNo, holderName, and balance, and provides public member functions to deposit, withdraw, and get the balance of the account. The private access specifier ensures that the data members can only be accessed and modified through these member functions, thereby achieving encapsulation.