簡單的一對多流暢，nhiberante

Question

我有簡單的一個一對多的關係

public class Product 
{ 
    public virtual Guid Id { get; set; } 
    public virtual string Name { get; set; } 
    public virtual string Category { get; set; } 
    public virtual bool Discontinued { get; set; } 
    public virtual IList<ProductCampaignTargeting> Targetings { get; set; } 
} 

public class ProductCampaignTargeting 
{ 
    public virtual Guid ID { get; set; } 

    public virtual int TargetType { get; set; } 

    public virtual string TargetValue { get; set; } 

    public virtual Product Product { get; set; } 
} 

與映射：

class ProductCampaignTargetingMap : ClassMap<ProductCampaignTargeting> 
{ 
    public ProductCampaignTargetingMap() 
    { 
     Table("campaign_targetings"); 
     Id(x => x.ID).GeneratedBy.Guid(); 

     Map(x => x.TargetType).Column("target_type"); 
     Map(x => x.TargetValue).Column("target_value"); 

     References(x => x.Product).Column("campaign_id_fk"); 
    } 
} 

class ProductMap: ClassMap<Product> 
{ 
    public ProductMap() 
    { 
     Table("Product"); 
     Id(x => x.Id).Column("id").GeneratedBy.Guid(); 

     Map(x => x.Name).Column("Name"); 
     Map(x => x.Category); 
     // check why inverse doens't work 

     HasMany(x =>   x.Targetings).KeyColumn("campaign_id_fk").Cascade.AllDeleteOrphan().AsBag(); 
    } 
} 

，它是工作 - 但孩子（很多）表用兩個命令更新 - 插入然後更新 當我想將其更改爲一個命令時，我使用反向（）選項 - 但隨後外鍵填充爲空，我在這裏丟失了什麼？

target.Product = product; 
product.Targetings.Add(target); 

這是原因之一，很多NHibernate的開發者推薦暴露：當您使用逆，因爲你必須添加ProductCampaignTargeting到集合時維持關係的雙方

Answer 1

外鍵爲空集合爲IEnumerable或只讀和封裝的添加和刪除方法：

void AddTarget(ProductCampaignTargeting target) 
{ 
    target.Product = this; 
    Targetings.Add(target); 
}