C# - Top 10 New Features (Part 1 Of 4)

Pankajkumar Patel

7y22.1k14100Article

C#.NETNew Key Features and Enhancements

14 Comments

Join the conversation! Your thoughts help the community grow.

Ryder6y ago
Nice one...
- Pankajkumar Patel6y ago
  Thanks Ryder for the feedback
Shailesh Pathak7y ago
Very nice..You are the inspiration of young people who has less experience in . Net...Well done ..Great job
- Pankajkumar Patel7y ago
  Thanks Shailesh Pathak for the feedback
Dhruvik Sathvara7y ago
Nice article...
- Pankajkumar Patel7y ago
  Thanks Dhruvik Sathvara for the feedback
Sourav Kumar Das7y ago
Nice Article.
- Pankajkumar Patel7y ago
  Thanks Sourav Kumar Das for the feedback
Arvind Kataria7y ago
Nice article ...!!!
- Pankajkumar Patel7y ago
  Thanks Arvind Kataria for the feedback
Shankar7y ago
Good one but what is advantage of this feature? Please add the same on your next feature explanations , what was not accomplished with out this feature or it is another way of doing same things?
- Pankajkumar Patel7y ago
  Thanks Shankar for the feedback, actually I have already submitted all series articles, but even though let me chek how can I do that
Shrimant Telgave7y ago
Nice article..
- Pankajkumar Patel7y ago
  Thanks Shrimant Telgave for the feedback

Article Overview

Background

How to compile/test with C# 8.0 in MS Visual Studio OR online
Key features and enhancements to C# 8.0
Switch Expression feature

Pre-requisites
How to compile/test with C# 8.0 in MS Visual Studio OR online

MS Visual Studio
Online tool

Key features and enhancements to C# 8.0

Switch Expressions
Indices and Ranges
Default Interface Members
Static Local Functions
Using Declarations
Nullable Reference Types
Readonly Struct Members
Null-Coalescing Assignment
Async Streams
Property, Tuple, and Positional Patterns

Switch Expression feature

Points
Example

Summary

Background

There was a situation where I had to know all the key important features and enhancements in C# 8.0. There are a number of articles and blogs where you can find detailed explanations of new features of C# 8.0.

Hence, to understand each one in detail, I went through various sites instead of one single place. So, here I am putting all the key details along with key points as well as examples with code in one place. This way, you can get most of all information from a single place.

I have divided this whole article into 4 parts for making it easy to understand with step by step movement to go ahead.

This article mainly focuses on three key things.

How to compile/test with C# 8.0 in MS Visual Studio OR online
Key features and enhancements to C# 8.0
Switch Expressions

Here, I have kept all the implementation details along with a complete example.

Prerequisites

You should have a basic knowledge of C#.

How to compile/test with C# 8.0 in MS Visual Studio OR online

First of all, before you start, you have to make the environment ready which can compile your C# 8.0 code.

There are two ways of doing this.

MS Visual Studio
Online tool

MS Visual Studio

Go to “Advanced Build Settings” and set “Language version” to “C# 8.0 (beta)”.

Online

There are various online tools where you can write, compile, and execute your code online. I am using “C# Online Compiler | .NET Fiddle” where you have to set “Compiler” to “.NET Core 3.0”.

Key features and enhancements to C# 8.0

C# 8.0 added the following key features and enhancements to the C# language.

Switch Expressions
Indices and Ranges
Default Interface Members
Static Local Functions
Using Declarations
Nullable Reference Types
Readonly Struct Members
Null-Coalescing Assignment
Async Streams
Property, Tuple, and Positional Patterns

Now, let us discuss each feature one by one in detail.

For your reference, I have kept all the examples in a single .cs file and uploaded them with this article.

Switch Expression feature

Below are the key syntax improvements:

Bodies are expressions, not statements.
Case and : elements are replaced with =>. It is more concise and intuitive.
Variable comes before the switch keyword. It is visually easy to distinguish the switch expression from the switch statement.
Default case is replaced with a _ discard.

Now, let us understand by examples.

Example-1

var (a, b, option) = (10, 5, "+");
var example1 = option switch
{
"+" => a + b,
"-" => a - b,
_ => a * b
};
Console.WriteLine(example1);

Example-2

var value = 25;
int example2 = value switch
{
_ when value > 10 => 0,
_ when value <= 10 => 1
};
Console.WriteLine( example2);

Example-3

Calculation c1 = new Calculation(50, 10, "*");
c1.print();
Calculation c2 = new Calculation(50, 10, "+");
c2.print();
public class Calculation
{
public Calculation(int a, int b, string operation)
{
this.FirstNumber = a;
this.SecondNumber = b;
this.Operation = operation;
this.ResultNumber = this.Operation switch
{
"+" => this.FirstNumber + this.SecondNumber,
"-" => this.FirstNumber - this.SecondNumber,
"/" => this.FirstNumber / this.SecondNumber,
"*" => this.FirstNumber * this.SecondNumber,
_ => -1
};
}
public int FirstNumber { get; set; }
public int SecondNumber { get; set; }
public string Operation { get; set; }
public int ResultNumber { get; set; }
public void print()
{
Console.WriteLine($"{this.FirstNumber} {this.Operation} {this.SecondNumber} = {this.ResultNumber}");
}
}

Summary

Now, I believe you will be able to compile/test with C# 8.0 in MS Visual Studio OR online, you know the key new features and enhancements to C# 8.0, and you understand the Switch Expression feature.

In my next article, I will cover the next three features such as "Indices and Ranges", "Default Interface Members", and "Static Local Functions".