ValueObject

Base class for immutable value objects.

Concept

Value Objects are DDD patterns where:

• Identity does not matter, only values
• Immutable after creation
• Equality based on all properties
• No side effects

Methods

Method	Description
GetEqualityComponents()	Override to return equality properties
Copy()	Creates a shallow copy
Equals(object?)	Value-based equality
GetHashCode()	Hash based on values

Usage

public class Email : ValueObject
{
    public string Value { get; }

    public Email(string value)
    {
        Guard.ValidEmail(value);
        Value = value.ToLowerInvariant();
    }

    protected override IEnumerable<object?> GetEqualityComponents()
    {
        yield return Value;
    }
}

Examples

• Email, Address, Money
• DateRange, Coordinates
• Any immutable concept