rstropek

<Window x:Class="HelloXaml.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:HelloXaml"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
<!-- 
      +=== Will become an object of this class

rstropek

<Window x:Class="MachineMonitor.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:MachineMonitor"
        mc:Ignorable="d"
        Title="Machine Monitor" Height="450" Width="800">
    <Window.Resources>
        <Style TargetType="local:TemperatureChart">

rstropek

using System;

var p = new Person("Foo", "Bar", 42);
// The following line does not work because records are immutable
// p.LastName = "Baz";
Console.WriteLine(p.FirstName);

var b = new Product("Bike", "Mountainbike", 499m);
Console.WriteLine(b.Name);

rstropek

using System;

var v1 = new Vector2d(1d, 2d);
v1.X = 3d; // This works because get and set are generated by default
Console.WriteLine(v1.X);
Console.WriteLine(v1); // record structs implement ToString

var v2 = v1 with { X = 4d }; // We can use the with keyword
Console.WriteLine(v2.X);

rstropek

using System;
using System.Text;

var p1 = new Point(1d, 2d);
// p1.X = 3d; // This does not work because readonly records are immutable
Console.WriteLine(p1);

// Note: At the time of writing, deconstruct can be compiled on sharplab.io, but cannot be executed.
//       If you want to run this code on sharplab.io, comment the following statement.
var (x, y) = p1; // Deconstruction works similar to record classes.

rstropek

using System;

ReadOnlySpan<Vector2d> vectors = stackalloc Vector2d[] { new(1d, 1d), new(2d, 2d), };
Console.WriteLine(AddAll(vectors));

static T AddAll<T>(ReadOnlySpan<T> addables) where T: IAddable<T>
{
    var result = T.Zero;
    foreach (var a in addables) result += a;
    return result;

rstropek

using System;

var app = new EndpointConventionBuilder();

// Traditional way of defining a function with an attribute
[HttpGet("/")] int GetAnswer() => 42;
app.MapAction((Func<int>)GetAnswer);

// Now, we can remove the type cast:
app.MapAction(GetAnswer);

rstropek

#nullable enable

using System;
using System.Runtime.CompilerServices;

var x = 5;
Verify.Lower(x * 2, Convert.ToInt32(Math.Floor(Math.PI)));

public static class Verify
{

rstropek

using System;

const string s1 = $"abc";
const string s2 = $"{s1}edf";
Console.WriteLine(s2);

DoSomething_Old(42);
DoSomething_VeryOld(42);

[Obsolete($"Use {nameof(DoSomething_New)} instead")]

rstropek

using System;
using System.Collections.Generic;

var numbers = new List<int>() { 1, 2, 3, 5, 8 };

// List pattern
if (numbers is { 1, 2, 3, 5, 8 })
{
    Console.WriteLine("Fibonacci");
}