C# Records: Immutable Data Types That Simplify Code and Testing

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C# Records were introduced with C# 9 in November 2020, offering a concise way to define immutable data models using minimal code. Unlike traditional classes, Records are immutable by default, meaning their properties can only be assigned at initialization and cannot be changed afterward. A key distinction is that Records use value-based equality rather than reference-based equality, eliminating the need to manually implement Equals and GetHashCode methods. This makes unit testing simpler and reduces boilerplate code compared to writing equivalent immutable classes. Records can also include custom validation logic, making them suitable beyond simple data containers.

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