define an aggregateroot in csharp

In domain-driven design, an Aggregate Root is a concept that defines a cluster of associated objects that must be treated as a single unit. The root entity controls access to other objects within the same aggregate, ensuring consistency of behavior and data integrity.

To define an Aggregate Root in C#, the first step is to define an interface that represents the behavior of the root entity:

main.cs
public interface IAggregateRoot
{
     Guid Id { get; }
}
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This interface defines the contract that all Aggregate Roots in our system must adhere to: they must have a unique identifier, represented as a GUID.

Next, we define the root entity using a class that implements this interface. Here's an example implementation of a Product Aggregate Root:

main.cs
public class Product : IAggregateRoot
{
    public Guid Id { get; private set; }
    public string Name { get; set; }
    public int Price { get; set; }

    public Product(Guid id, string name, int price)
    {
        // Ensure that the root entity is initialized with a unique identifier
        Id = id;
        Name = name;
        Price = price;
    }

    // Define behavior for the root entity
    public void UpdatePrice(int newPrice)
    {
        if (newPrice < 0) throw new ArgumentException("Price cannot be negative");
        Price = newPrice;
    }
}
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In this implementation, the Product class implements the IAggregateRoot interface and defines its own properties and behavior. Other objects in the same aggregate (such as OrderItems that contain these Product objects) can only interact with the root entity, ensuring that all changes to the Product are done through the root entity and not directly.