Let’s catch up with C#! Exciting new features in C# 9, 10, 11 and 12!

on YouTube ↗55m

" summary

Walks through concrete C# 8–12 changes with compile-time examples in Visual Studio: nullable reference types now warn by default and work with required and init-only so object initializers and JSON deserialization must set properties or the compiler complains; records and with-expressions give value equality and cheap immutability; collection expressions and spread element build target-typed lists but allocate copies; shows interceptors replacing calls at compile time (used in ASP.NET Core) and notes the withdrawn parameter-null-check proposal.

AI-written summary · about

" chapters (12)

1. 0:00Introduction
2. 1:50Nullable reference types
3. 8:32Async streams basics
4. 12:45C# 9 records and top-level
5. 19:10Pattern matching in C# 9
6. 27:48C# 10 minimal APIs
7. 32:01C# 11 list patterns
8. 38:22C# 12 primary constructors
9. 46:13C# 12 interceptors
10. 48:01C# 13 preview
11. 53:19Adopting new C# features
12. 54:24Q&A

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