domain-driven-design - 通过聚合根 : simple example? 访问实体

Question

您能否展示通过 ita 聚合根访问聚合中实体内容的简单示例？我不清楚您将如何表示聚合权限以反射(reflect)这些概念。蒂亚。

Answer 1

您通常会将其封装在聚合在其契约(Contract)中公开的命令中。

例如，对于 Order Aggregate，您可以使用从 GUI 获得的数据添加 OrderLine。

// This is the Order Aggregate Root
public class Order
{
    private readonly int id;
    private readonly Customer customer; // Customer is another Aggregate
    private readonly IList<OrderLine> orderLines;
    private readonly IOrderLineFactory orderLineFactory;

    public Order(int id, Customer customer, IOrderLineFactory orderLineFactory)
    {
        this.id = id;
        this.customer = customer;
        this.orderLines = new List<OrderLine>();
        this.orderLineFactory = orderLineFactory;
    }

    public void AddOrderLine(Item item, int quantity)
    {
        OrderLine orderLine = orderLineFactory.Create(this, item, quantity);
        orderLines.Add(orderLine);
    }
}