A regular discussion I have with junior developers is about loosely coupled code. by Open for Extension Closed for Modification. Photo: Unsplash. O — Open/Closed Principle. SOLID Principles by Examples: Open/Closed This post analyzes and provides a real-world example of the Open/Closed principle, one of the five SOLID principles for programming. Tagged csharp, ocp in c#, open closed principle, open closed principle in csharp Example Below example violates the rules of SRP & OCP. Open Closed Principle: Real-Life Example with Refactoring. This principle suggests that “classes should be open for extension but closed for modification”. The solution is 100% open for extension and closed for modification. Why especially with .Net, it is important and the benefits it can bring. should be open for extension but closed for modification. Prefer extension over modification (C# Code example).Bad Way. The Open/Closed Principle. A module will be said to be open if it is still available for extension. ... o is for open/closed principle ... behaviors. Now you know that Open-Closed means that your code is open to be extended by new functionalities and closed in terms of changing the source code, but appending to it. This violates the Open Closed Principle, because at the moment there are 2 types of customer, if we want to add another customer type we have to add an if else statement below and will modify the existing code. The Open-Close principle (OCP) is the O in the well known SOLID acronym.. Bertrand Meyer is generally credited for having originated the term open/closed principle, which appeared in his 1988 book Object Oriented Software Construction.Its original definition is. The Open/Closed Principle, created by Bertrand Meyer in 1988, states: Software entities (classes, modules, functions, etc.) Suppose we are going to design a class for Shopping cart, Generally we need 3 basic functionalities for that. It is relatively easy to describe certain topics that way: a dog barks, a cat meows, but they all make a sound. The Open/Closed Principle, which I explained in a previous article, is one of the key concepts in OOP that enables you to write robust, maintainable and reusable software components.But following the rules of that principle alone is not enough to ensure that you can change one part of your system without breaking other parts. When I was studying IT, the examples in the object-oriented programming course usually had something to do with the animal kingdom. The Open Closed Principle represents the “O” of the five SOLID software engineering principles to write well-designed code that is more readable, maintainable, and easier to upgrade and modify. The Open/Closed Principle Real World Example 20 March 2018. That’s why I searched for some examples of these issues in Open Source projects and use them in this series. Notice that the single responsibility principle is also applied. 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