Exceptions and Member functions in C++

Member Functions

Member functions are declared within the class definition and work on the class's data members. The definition of member functions can occur either within or outside the class's definition.

If the member function is declared within the class definition, it can be defined directly; however, if it is defined outside the class, we must use the scope resolution:: operator in conjunction with the class name and function name.

For example:

class Square
{
    public:
    int side;
 
    // Declaring function getArea
    // with no argument and return type int.
    int getArea();     
};

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If we declare a function inside a class, then we don’t need to declare it beforehand, we can directly define the function inside the class, 

class Square
{
    public:
    int side;
 
    // function getArea returns the area of the square
    int getArea(){
      return side*side; 
    }     
};

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If we want to declare a member function outside the class, then we need first define the function inside the class,

class Square
{
    public:
    int side;
    int getArea();   
};

int Square:: getArea(){
   return side*side;
}

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Calling class Member function

Similarly, to access a data member in the class, we will use the dot operator to access the public member functions via the class object (.). 

int main(){
  Square S;
  S.side = 5; // initialising the side value
  cout<<"The area of the square is:"<<S.getArea()<<endl; 
}

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Frequently Asked Questions

What are classes and objects in C++?

A class is a data type that is specified by the user and has data members and member methods. Data members are data variables, and member functions are used to operate on these variables.

An object is a class instance. Because a class is a user-defined data type, an object is sometimes referred to as a variable.

What is a virtual function in C++?

A virtual function is a base class member function that you redefine in a derived class. The virtual keyword is used to declare a virtual function. C++ chooses which function is to be executed at runtime depending on the type of the object referenced by the base class pointer when the function is made virtual.

What are C++ access specifiers?

In C++, there are three types of access specifiers:

Public: All the data members and member methods are accessible outside the class.

Protected: All data members and member methods are accessible inside the class and to the derived class.

Private: All data members and member methods are not accessible outside the class.

Conclusion

This article discussed the concept of exceptions and member functions in C++. We have discussed them using suitable examples to provide clarity to you. I hope you have better understood the above topic after reading this blog. 

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