ASP.NET C#实体框架-如何正确更新外键？-第二部分

这个问题就像我演讲的第二部分

以下是我学到的并希望成为现实的事情：

不要将数据实体上下文用作静态上下文

使用后处理数据上下文-通常在一次之后-

将参数传递到更新实体方法而不是实体 （我要解释一下，我的十字路口就在这里）

这是我修改过的代码：

public class ManagerBase
    {
        private NoxonEntities _entities = null;

        public NoxonEntities Entities
        {
            get
            {
                if (_entities == null)
                    _entities = new NoxonEntities();

                return _entities;
            }
        }
    }

//Managers uses ManagerBase class as a Base class
MemberManager currentMemberManager = new MemberManager();
currentMemberManager.Save(memberId, username, password, languageId);


//MemberManager class
public Member Save(long memId, string username, string password, int langId)
        {
            using (var Context =   base.Entities)
            {
                var Data = Context.Member.First(c => c.Id == memId);

                Data.Username = username;
                Data.Password = password;
                Data.Language = Context.Language.First(c => c.Id == langId); //Gets the foreign entity

                Context.SaveChanges();

                return Data;
            }
        }

这毫无例外。但是通常这种保存方法是通过接口实现的方法。因此，我宁愿将一个对象值传递给SAVE方法，也不愿像上面那样传递所有字段。 例如，我想用这个：

//Member is an EntityFramework Object which was created during EF Model when I added by visual studio
//Filter is the method that returns an EntityFramework Object from EF (and eventually database) with given some arguments
//SomeArguments could be  MemberId = 2
Member modifiedMember = currentMemberManager.Filter(someArguments);
modifiedMember.UserName = "newvalue";
currentMemberManager.Save(modifiedMember);

在SAVE方法中，我可能会这样使用：

public Member Save(Member modifiedMember)
            {
                using (var Context =   base.Entities)
                {
                    var Data = Context.Member.First(c => c.Id == modifiedMember.Id);

                    Data.Username = modifiedMember.Username;
                    Data.Password = modifiedMember.Password;
                    Data.Language = Context.Language.First(c => c.Id == modifiedMember.LanguageId); //Gets the foreign entity

                    Context.SaveChanges();

                    return Data;
                }
            }

如果我要像上面一样使用它，我想我不应该使用传递对象EF object，而应该使用我将要编写的其他类来将参数映射到EF成员实体

第一个问题：这是一个好方法吗？

public class MyMember
{
    public long Id { set; get; }
    public string Username { set; get; }
    public string Password { set; get; }
    public int LanguageId { set; get; }
}

MyMember.Username = "NewValue";
MyMember.LanguageId = 4; //4 as in new value
currentMemberManager.Save(MyMember); //As you can see MyMember is not an EF Entity in here

但这将需要很长时间，因为已经有一些书面代码

第二个问题：我不能在外部使用EF实体对象并在那里修改它以将其保存在MemberManager类中吗？

public class MyMember
{
    public long Id { set; get; }
    public string Username { set; get; }
    public string Password { set; get; }
    public int LanguageId { set; get; }
}

MyMember.Username = "NewValue";
MyMember.LanguageId = 4; //4 as in new value
currentMemberManager.Save(MyMember); //As you can see MyMember is not an EF Entity in here

再次感谢您事先提供的帮助。

以下是答案：

---

我感谢那些帮助我的人。

我在这个链接上找到了答案。[ [1]: