如何使用GraphDiff更新相关实体？

Question

我有以下型号:

public class Customer
{
    public int Id {get; set;}
    public string Name {get; set;}
    public int AddressId {get; set;}
    public virtual Address Address {get; set;}
    public virtual ICollection<CustomerCategory> Categories {get; set;}
}

public class CustomerCategory
{
    public int Id {get; set;}
    public int CustomerId {get; set;}
    public int CategoryId {get; set;}
    public virtual Category Category {get; set;}
}

public class Address
{
    public int Id {get; set;}
    public string Street{get; set;}
    public virtual PostCode PostCode {get; set;}
}

从上面,并使用GraphDiff,我想更新客户聚合如下:

dbContext.UpdateGraph<Customer>(entity, 
            map => map.AssociatedEntity(x => x.Address)
                      .OwnedCollection(x => x.Categories, with => with.AssociatedEntity(x => x.Category)));

但上面没有更新任何东西!!

在这种情况下使用GraphDiff的正确方法是什么？

Answer 1

GraphDiff基本上区分了两种关系:拥有和关联.

拥有可以被解释为"成为"的一部分,意味着拥有的任何东西都将与其所有者一起插入/更新/删除.

GraphDiff处理的另一种关系是关联的,这意味着在更新图形时,GraphDiff只会更改与关联实体本身的关系,而不会更改关联实体本身的关系.

当您使用该AssociatedEntity方法时,子实体的State不是聚合的一部分,换句话说,您对子实体所做的更改将不会被保存,只会更新父navegation属性. 如果要保存对子实体的更改,

请使用此OwnedEntity方法,因此,我建议您尝试这样做:

dbContext.UpdateGraph<Customer>(entity,  map => map.OwnedEntity(x => x.Address)
                                                   .OwnedCollection(x => x.Categories, with => with.OwnedEntity(x => x.Category)));
dbContext.SaveChanges();