Records

Learn C# record types — a concise way to model immutable data with built-in value equality.

What is a Record?

Introduced in C# 9, a `record` is a reference type designed for modeling immutable data concisely — it automatically generates a constructor, properties, and value-based equality.

record Person(string Name, int Age);

var person = new Person("Diya", 28);
Console.WriteLine(person); // ToString() is auto-generated too
Console.WriteLine(person.Name);

Output

Click Run to see what this code prints.

Value Equality

Unlike a regular class (which compares by reference), two records with identical property values are considered equal.

var p1 = new Person("Diya", 28);
var p2 = new Person("Diya", 28);

Console.WriteLine(p1 == p2); // True — value equality!

The with Expression

`with` creates a new record based on an existing one, copying every property except the ones you override — ideal for immutable data.

var updated = person with { Age = 29 };
Console.WriteLine(updated);
Console.WriteLine(person); // original is unchanged

Output

Click Run to see what this code prints.

Records vs Classes

record

Value equality by default
Concise, auto-generated ToString()
Ideal for DTOs and immutable data

class

Reference equality by default
Full control over behavior
Ideal for entities with identity and mutable state

FAQs

Are records always immutable?

By default their properties are init-only (settable only at creation), but you can still declare a mutable record if you explicitly need one — immutability is the convention, not a hard rule.

Summary

Records are a concise way to model immutable data.
They compare by value, not reference, by default.
`with` creates a modified copy without mutating the original.

Next Lesson →