.NET Version History (up to .NET 9)

public class C<T> where T : allows ref struct

class BankAccount(string accountID, string owner)

string[] names = ["Julia", "Anna", "Thomas"];
// and
string[] allNames = [.. names, .. moreNames];

var IncrementBy = (int source, int increment = 1) => source + increment;

[Experimental("1234")]

sequence is [1, 2, 3]

""" hello """;

{ Prop1.Prop2: pattern }

namespace MyNamespace;
// instead of nesting

(x, int y) = point;

public record struct Point
{
    public double X { get; init; }
    public double Y { get; init; }
    public double Z { get; init; }
}

int YearOfBirth { get; init; }

record Person(string FirstName);

(_, _) => 0

shape switch { { Point: { Y : 100 } } => "Y is 100"};

(animal, other) switch { (Animal.Bird, _} => "It's a Bird" };

shape switch { Rectangle (100, 100) => "It's a square" };

if (item is List<T> value)
{
// ...
}

GetEmployeeDetails(out string EmployeeName);

var t = ("post office", 3.6);
// and
var (destination, distance) = t;

int a = 1;
// and
ref int alias = ref a;

(_, _, area) = city.GetCityInformation(cityName);

var binaryLiteral = 0b_0010_1010;
// and
var bigNumber = 123_456_789;

string first = args.Length >= 1 ? args[0] : throw new ArgumentException("Please supply at least one argument.");

catch (ExceptionType [e]) when (expr)

string FirstName { get; set; } = string.Empty;

void DisplayName() => Console.WriteLine(ToString());

Console.WriteLine($"Hello {name}");

var foo = new IndexableClass { [0] = 10 };

try
{
    // something that throws
}
catch
{
await Task.Delay(1000); // using await in catch block
}

public void TraceMessage(
    string message,
    [CallerMemberName] string memberName = "",
    [CallerFilePath] string sourceFilePath = "",
    [CallerLineNumber] int sourceLineNumber = 0)
{
// ...
}

dynamic dyn = 1;

ExampleMethod(3, optionalint: 4);
// where
int optionalint = 10

public string Name { get; set; }

var

var v = new { Amount = 108, Message = "Hello" };

partial void OnSomethingHappened(String s)

new Cat { Age = 10
// and
new List<int> { 0, 1, 2};