Modern C# Features

Modern C# Features

C# keeps evolving. These modern features make code shorter, safer, and more expressive.

Top-level statements

Skip the ceremony - just write the code:

Console.WriteLine("Hello, World!");

This is the whole file. The compiler generates the Main method for you.

Expression-bodied members

Short methods and properties with =>:

public int Square(int x) => x * x;
public string Name { get; set; } = "Ada";

Records

A record is a class designed for immutable data - value semantics and value equality come free:

record Person(string Name, int Age);

var p1 = new Person("Ada", 36);
var p2 = new Person("Ada", 36);
Console.WriteLine(p1 == p2);   // True - value equality

Null-conditional operator

?. only calls the member if the object isn't null:

string? name = null;
Console.WriteLine(name?.ToUpper() ?? "empty");   // empty

string interpolation

You've seen

quot;{x}" - it's the modern way to build strings.

switch expressions

An expression version of switch:

string DayName(int d) => d switch
{
  1 => "Monday",
  2 => "Tuesday",
  _ => "Unknown"
};

TL;DR

• Top-level statements drop the boilerplate.
• Records give immutable, value-equal data.
• ?. safely handles nulls.
• Switch expressions and interpolation keep code tidy.