Are you new to programming, or perhaps you’ve just started exploring a specific programming language and its features.
Perhaps even as an experienced programmer, you’ve not yet had the opportunity to program in C++. Whatever the case may be, if you’re reading this article, it means that there’s something about inheritance in C++ that has piqued your interest.
Inheritance is a useful feature of many programming languages. It allows a programmer to create classes that are based on another pre-existing class with similar code and functions.
This streamlines code development by allowing subclasses to inherit methods from their parent classes rather than writing the same code again and again.
In this article, we will look at inheritance in C++, why it is used, how to use it in our programs, and some examples of how we can implement inheritance in our code. Let’s get started!
What is Inheritance in C++?
Inheritance, in the context of programming languages, is the process of one class gaining the properties of another class. In C++, this means that a new class has been created that is built upon an existing class.
In more detail, inheritance allows a programmer to create a new class that is based on an existing class, usually because they have a lot of common code and functionality.
As an example, let’s say we have a class called “Human” and it has a method called “Run”, which takes in a parameter of “Speed”. The Human class also has a field called “Health”, which is of type “Int”.
Why use Inheritance?
Inheritance is used to streamline code development by allowing subclasses to inherit methods and fields from their parent classes.
Why would we want to do this though? Wouldn’t writing each piece of code from scratch, along with all of the methods and fields, be a more efficient approach? The answer to this question lies in the “Design Paradigm”.
If a person were to design a car, they’d find that there are many components that are common to all cars, but there are also components that are unique and specific to each model of car.
The same goes for classes in programming. Common methods that are applied to all classes are called “General Methods”, whereas specific methods that are limited to one class are called “Instance Methods”.
Inheritance allows a programmer to create a new class that is built upon an existing class, usually because they have a lot of common code and functionality.
For example, if we have a class called “Human” and it has a method called “Run”, which takes in a parameter of “Speed”. The Human class also has a field called “Health”, which is of type “Int”.
If we also have another class known as “Runner”, which has a method called “Run” that also takes a parameter of “Speed”, we would be duplicating the code for running since the Human class already has a “Run” method. Instead, we can create a new class called “Runner”, which is based on the Human class.
This will allow the Runner class to inherit the methods and fields of the Human class, thereby creating a streamlined code that is easier to manage.
How to use Inheritance in C++?
In order to use inheritance in our code, we first have to decide which class we want to be the parent class. The parent class must have a “Public Interface”, which means that the class must have all of its methods and fields declared as “Public”.
The next step is to create the subclass, which will be a new class that is based on the parent class. The subclass will have “Public Inheritance”, which means that it too must have all of its methods and fields declared as “Public”.
When you inherit from a class, the subclass automatically has all of the class’s Public Methods and Fields. We can call these using the same syntax that we would use with any other method or field.
When to Use Inheritance in C++?
Inheritance is a useful tool, but as with many things in life, it’s not appropriate to use every time. It’s important to look at the advantages and disadvantages of inheritance in C++ before deciding whether it’s the right tool for the job.
Advantages of Inheritance:
– Reusable Code – Inheritance allows us to build upon existing code, so it’s very easy to reuse code that’s already been written.
– Shorter Code – Inheritance can help to reduce the length of our code, especially when we’re trying to extend an existing class.
– Modularity – Inheritance also helps to increase the modularity of our code.
– Code Readability – Inheritance can help to improve the code readability, which will make it easier to understand by other programmers.
– Early Design Decision – Finally, inheritance can be used early on in the design process to help with generalization and specialization.
Disadvantages of Inheritance:
– More Complexity – Perhaps the biggest disadvantage of inheritance is that it can make our code more complex. This is because when we inherit from a class, everything in the parent class is available to us and it becomes harder to know where to look if we have to make specific changes.
Examples of Inheritance in C
Here we will take a look at some examples of inheritance in C. We’ll start by creating a parent class and then create a subclass based on it.
Parent Class: Let’s say we have a class named “Bird”. This class will be our parent class and it has a “Fly” method, which takes in a parameter of “Speed”. The Bird class also has a field called “Health”, which is of type “Int”.
Subclass: Now let’s take a look at the “Swallow” class. This is our subclass and it is based on the Bird class. The Swallow class has a method called “Fly” that also takes in a parameter of “Speed”.
This is the method from the parent class and the Swallow class inherited it from the Bird class. The Swallow class also has a field called “Health”, which is of type “Int”.
In this article, we’ve explored inheritance, what it is in C++, and why it’s used. We’ve also looked at how to use inheritance in our code and some examples of inheritance in C.
Inheritance is a useful tool that can be applied to code development in many different ways. That being said, it can also have some disadvantages, so it’s important to understand what they are before using it.