使用Entity Framework ver时,我已成功使用此代码检查所有关系。 5。 (来自yildizm85,Entity Framework: Check all relationships of an entity for foreign key use)
public bool IsUnitNameInRelationship(UnitName unitName)
{
bool hasRelation = false;
var allRelatedEnds = ((IEntityWithRelationships)unitName).RelationshipManager.GetAllRelatedEnds();
foreach (var relatedEnd in allRelatedEnds)
{
if (relatedEnd.GetEnumerator().MoveNext())
{
hasRelation = true;
break;
}
}
return hasRelation;
}
升级到EF 6.1.1后失败。 错误消息是:
Unable to cast object of type 'System.Data.Entity.DynamicProxies.UnitName_F023365757AB452259D6FFA34E2DC147E423592BFB4A49619F41A60AA3AF5ECA' to type 'System.Data.Objects.DataClasses.IEntityWithRelationships'.
使用EF 6.1.1检查所有关系是否有更好的方法?
答案 0 :(得分:2)
在将实体的动态代理实例转换为EF 6.1.3的IEntityWithRelationships
接口时,我遇到了同样的问题!
而且由于我没有父母的所有关联实体的导航属性,因此我想到了以下基于反射的代码来最终获得RelationshipManager
实例:
var entityProxy = DbContext.FooBars.First(fb => fb.Id == someId);
var proxyType = entityProxy.GetType();
var wrapperField = proxyType.GetField("_entityWrapper");
var wrapper = wrapperField.GetValue(entityProxy);
var wrapperType = wrapper.GetType();
var relManProp = wrapperType.GetProperty("RelationshipManager");
Debug.Assert(relManProp != null, nameof(relManProp) + " != null");
var relMan = (RelationshipManager)relManProp.GetValue(wrapper);
var allEnds = relMan.GetAllRelatedEnds();
foreach (var relatedEnd in allEnds)
{
Debug.Print("RELATIONSHIP-NAME:" + relatedEnd.RelationshipName);
}