C# 13 Unleashed: Live Demos of my Top 10 Cutting-Edge Features!

What if `params` wasn't limited to arrays? See this and nine other game-changing features coming in C# 13.

#1about 3 minutes

A brief history of C# from version 1 to 12

Key features like generics, LINQ, async/await, and records were introduced in major C# versions leading up to C# 13.

#2about 1 minute

How to set up your environment for C# 13

To use C# 13 features, you must install the .NET 9 SDK and use a recent preview version of Visual Studio 2022.

#3about 3 minutes

Using the enhanced params modifier with collections

The `params` modifier in C# 13 is no longer limited to arrays and can now be used with any collection type, including `ReadOnlySpan` or custom types.

#4about 2 minutes

Using the caret operator in object initializers

The caret operator (`^`) can now be used within object initializers to set collection elements from the end, simplifying code for tasks like countdowns.

#5about 3 minutes

Simplifying terminal output with the new escape sequence

C# 13 introduces the `\e` escape sequence as a more intuitive and less error-prone way to represent the escape character for terminal and console applications.

#6about 3 minutes

Separating definitions with partial properties and indexers

Partial properties and indexers allow you to split a property's declaration from its implementation across different parts of a partial class, which is useful for source generators.

#7about 6 minutes

Guiding overload resolution with a priority attribute

The `OverloadResolutionPriority` attribute allows library authors to guide the compiler in choosing a specific method overload, resolving ambiguities without breaking changes.

#8about 3 minutes

Improving thread synchronization with the new lock type

A new `System.Threading.Lock` type provides a more efficient and clearer way to handle thread synchronization in multi-threaded applications compared to traditional locking mechanisms.

#9about 4 minutes

Optimizing method group overload resolution

The compiler now handles method groups more efficiently by eliminating non-matching method candidates earlier in the process, improving performance in complex overload scenarios.

#10about 3 minutes

Using ref and unsafe contexts in async methods

C# 13 allows the use of `ref` local variables and `unsafe` contexts within async methods and iterators, with restrictions around `await` and `yield` boundaries to ensure safety.

#11about 2 minutes

Allowing ref struct types in generic parameters

You can now use `ref struct` types as generic type parameters by using the `allow-ref-struct` constraint, enabling more efficient generic algorithms.

#12about 3 minutes

Implementing interfaces with ref struct types

`ref struct` types can now implement interfaces, combining the performance benefits of `ref struct` with the abstraction provided by interfaces, though conversion to the interface type is restricted.