Design patterns are reusable and customizable solutions to problems that often arise in software design and development. The patterns you use and how you use them depend entirely on your own unique programs and problems. Learning design patterns will not only help you solve software design problems, but will make you a stronger developer and allow you and your team to communicate more efficiently and uniformly. Today, we’re going to take a look at some design patterns in C# and discuss their use cases and pros and cons.
We’ll cover:
Get up to speed with C#
This highly interactive C# course begins with a simple Hello World program, then proceeds to cover fundamental concepts such as conditional statements, loop statements, and methods in C#.
Design patterns were made to tackle common problems that arise within software design and software development when working with real-world app development. Design patterns are like customizable templates that can be applied to your code regardless of your preferred programming language. While they aren’t meant to be directly copied and pasted into your code, they provide you with high-level conceptual information that can help you solve your software design problems.
The same design pattern won’t look the same when applied to two different programs. This is where the customization comes in. You can think of a design pattern as a blueprint, providing you a high-level plan to guide you through your software design process, but giving you the power to implement the solution in a way that best fits your needs.
Note: Design patterns are different from algorithms. Algorithms clearly define a set of steps to help you solve a problem, while design patterns provide high-level descriptions.
There are many benefits to using design patterns within your software development environment. Some benefits include:
There are 23 Gang of Four (GoF) patterns that are considered the foundations for all other design patterns. They are separated into three main groups based on three common problem areas within software architecture: behavioral, creational, and structural.
There are many different types of design patterns that you can implement into your programs. Let’s take a look at nine of the 23 GoF design patterns in C# and .NET and discuss their use cases and pros and cons.
Behavioral design patterns are concerned with algorithms and assigning responsibilities to objects. First, we’ll take a look at the Chain of Responsibility design pattern.
The Chain of Responsibility pattern enables you to pass requests along a chain of handlers. When a handler receives a request, it decides whether to process the request or pass it to the next handler in the chain.
Use cases
Here are some use cases of the Chain of Responsibility design pattern:
Pros:
Cons:
The Command pattern turns requests into stand-alone objects containing all the information about the requests. This process allows you to:
Note: You can use the Prototype design patterns if you need to save copies of your Commands.
Use cases
Here are some use cases of the Command design pattern:
Pros:
Cons:
The Iterator pattern allows you to iterate through elements in a collection without exposing the underlying representation.
Use cases
Here are some use cases of the Iterator design pattern:
Pros:
Cons:
Creational design patterns provide you with different object creation mechanisms to increase the flexibility and reusability of your code. We’re going to take a look at three common creational design patterns, starting with the Abstract Factory design pattern.
The Abstract Factory pattern allows you to create families of related objects without indicating their concrete classes.
Use cases
Here are some use cases of the Abstract Factory design pattern:
Pros:
You can bring new variations of products into the application without changing the existing code
You can pull the product creation code to one place
You can avoid tight coupling between client code and products
Cons:
The Builder pattern allows you to build complex objects one step at a time and produce different representations of an object using the same construction code.
Use cases
Here are some use cases of the Builder design pattern:
Pros:
Cons:
The Factory Method pattern allows you to create objects in a superclass and allows subclasses to change the type of objects that will be created. It’s a specialization of the Template Method, which defines the framework of an algorithm in a superclass and allows the subclasses to override steps of the algorithm without changing the framework.
Use cases
Here are some use cases of the Factory Method design pattern:
Pros:
You can move the product creation code into one place
You can avoid tight coupling between the creator and the products
Cons:
Learn C# without scrubbing through videos or documentation. Educative’s text-based courses are easy to skim and feature live coding environments - making learning fun and efficient.
The Adapter pattern enables collaboration between objects with different interfaces.
Use cases
Here are some use cases of the Adapter design pattern:
Pros:
You can separate the interface from the business logic of your program
You can bring new adapters into the application without changing the existing code
Cons:
The Bridge pattern allows you to split large classes or sets of related classes into separate hierarchies that can be developed independently of one another.
Use cases
Here are some use cases of the Bridge design pattern:
Pros:
Cons:
The Composite pattern allows you to make objects into tree structures and work with those tree structures as individual objects.
Use cases
Here are some use cases of the Composite design pattern:
Pros:
Cons:
C# design patterns provide you with customizable and reusable solutions to common software design problems. The patterns you will work with will be dependent upon your individual needs and programs. Once you learn more about the different design patterns, you can begin implementing them into your programs. There are many more design patterns to learn such as:
Memento
Prototype
Singleton design pattern
Decorator
Flyweight
Constructor
To learn more about fundamentals of C#, check out Educative’s course C# for Programmers: A Practical Guide. In this hands-on course, you’ll start with learning the “Hello World!” in C#, and then move into more advanced concepts like classes, inheritance, interfaces, and delegates. By the end, you’ll feel confident using C# in your next project.
Happy learning!
Join a community of more than 1.3 million readers. A free, bi-monthly email with a roundup of Educative's top articles and coding tips.