richlander

const string Bar = "Bar";
const string DoubleBar = $"{Bar}_{Bar}";

WriteLine(DoubleBar);

richlander

.NET 6 Examples

• Record structs
• Readonly record structs
• Extended property patterns
• const interpolated string

Note: See .NET 5 examples

richlander

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net6.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

</Project>

richlander

Battery battery = new("CR2032", 0.235, 100);

WriteLine(battery);

while (battery.RemainingCapacityPercentage > 0)
{
    Battery updatedBattery = battery with {RemainingCapacityPercentage = battery.RemainingCapacityPercentage - 1};
    battery = updatedBattery;
}

richlander

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net6.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

</Project>

richlander

Battery battery = new("CR2032", 0.235, 100);

WriteLine(battery);

while (battery.RemainingCapacityPercentage > 0)
{
    battery.RemainingCapacityPercentage--;
}

WriteLine(battery);

richlander

namespace XUnitTestProject
{
    using Xunit;

    public static class SwitchStatementMapper
    {
        // Don't judge me, it's only for educational purposes :)
        public static bool Map(string str) => str switch
        {
            "true" => true,

richlander

Modernizing a codebase for C# 9

There are lots of cases that you can improve. The examples use nullable reference types, but only the WhenNotNull example requires it.

Use the property pattern to replace IsNullorEmpty

Consider adopting the new property pattern, wherever you use IsNullOrEmpty.

string? hello = "hello world";

richlander

.NET 5.0 Examples

The following are examples of various features.

• Modernizing a codebase for C# 9
• Top-level programs
• Various patterns of patterns
• Should rich go to the doctor
• Various patterns of records
• Records vs Classes (with init)

richlander

using System;
using System.Net.Http;
using System.Net.Http.Json;

string serviceURL = "https://localhost:5001/WeatherForecast";
HttpClient client = new();
Forecast[] forecasts = await client.GetFromJsonAsync<Forecast[]>(serviceURL);

foreach(Forecast forecast in forecasts)
{