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.Net 6

This page convers the most important changes introduced in .Net 6 (in my view).

New Features in .Net 6​

Performance Improvements​

There were a lot of performance improvements introduced in .Net 6. They are documented in this blog post. The achievable performance improvements are dependent on the used language features. For instance, the FileStream class has been entirely rewritten, which results in performance gains of over 100% in reading a file (.Net 6 vs .Net 5).

Overall these improvements can make a significant difference in the performance of the application. See these examples:

C# 10​

Version 10 of the C# Language has been introduced with .Net 6. Changes are discussed in this blogpost. TODO: Reference own writeup

Global using directives​

Global using directives let you specify a using directive just once and have it applied to every file that you compile.

Syntax:

global using System;
global using static System.Console;
global using Env = System.Environment;

Commonly used namespaces can now also be included by default by including implicit usings via MSBuild:

<ImplicitUsings>enable</ImplicitUsings>

File-scoped namespaces​

Namespaces now don't need to nest the encapsulating code in a block statement, if they apply for the whole file. Instead they can be declared like this:

namespace MyNamespace;

class MyClass { ... } // Not indented

Hot Reload​

Hot Reload enables you to make a wide variety of code edits to a running application, collapsing the time you need to spend waiting for apps to rebuild, restart, or to re-navigate to the same spot where you were after making a code change.

Instead of restarting the application it will detect changes on saving a file and almost instant-reload the changed application automatically.

Arm64​

.Net 6 supports development on the ARM64 architecture on Windows, Linux and MacOS. New Apple M1 chips are also supported

Single-file Apps​

In .NET 6, in-memory single file apps have been enabled for Windows and macOS. Before that they were only possible on Linux.

DateOnly and TimeOnly structs​

  • Each represent one half of a DateTime, either only the date part, or only the time part
  • DateOnly is ideal for birthdays, anniversary days, and business days
  • TimeOnly is ideal for recurring meetings, alarm clocks, and weekly business hours
  • Complements existing date/time types (DateTime, DateTimeOffset, TimeSpan, TimeZoneInfo).