The basic syntax and usage for a primary constructor is: public class Student(int id, string name, IEnumerable grades) C# 12 extends them to all classes and structs.

Primary constructors were introduced for records in C# 9 as part of the positional syntax for records. For example, you could use the parameters to initialize properties or in the code of methods and property accessors. Primary constructors let you add parameters to the class declaration itself and use these values in the class body. Primary constructors for non-record classes and structs Find out what else is coming for developers in Announcing.

To test out these features yourself, you can download the latest Visual Studio 17.6 preview or the latest. In addition to this overview, you can also find detailed documentation in the What’s new in C# article on Microsoft Learn. Default values for lambda expression parameters.Primary constructors for non-record classes and structs.

We’re excited to preview three new features for C# 12:

Visual studio 2022 download preview