Question

我想为分层结构化对象创建一个抽象类。

以下是我已经使用的内容，但现在我想将其设为通用

   public class EventBase 
{

    private EventBase _Parent;
    virtual public EventBase Parent
    {
        get
        {
            return _Parent;
        }
        set
        {
            _Parent = value;
        }
    }

    [ForeignKey("Parent")]
    private ICustomList<EventBase> _ChildList = new CustomList<EventBase>();
    virtual public ICustomList<EventBase> ChildList
    {
        get
        {
            return _ChildList;
        }
        set
        {
            _ChildList = value;
        }
    }
}

类似的东西：

  public class EventBaseGeneric
{

    private GenericTypeThatIsSetInTheInheritingClass _Parent;
    virtual public GenericTypeThatIsSetInTheInheritingClass Parent
    {
        get
        {
            return _Parent;
        }
        set
        {
            _Parent = value;
        }
    }

    [ForeignKey("Parent")]
    private ICustomList<GenericTypeThatIsSetInTheInheritingClass> _ChildList = new CustomList<GenericTypeThatIsSetInTheInheritingClass>();
    virtual public ICustomList<GenericTypeThatIsSetInTheInheritingClass> ChildList
    {
        get
        {
            return _ChildList;
        }
        set
        {
            _ChildList = value;
        }
    }
}

非常感谢你如何解决这个问题！

祝你好运， Fabianus

Answer 1

它看起来如下：

// T generic parameter must inherit EventBase<T>
public class EventBase<T>
    where T : EventBase<T>
{
    public virtual T Parent { get; set; }

    [ForeignKey("Parent")]
    public virtual ICustomList<T> ChildList { get; set; } = new CustomList<T>()
}

Answer 2

我找到了答案：

    public abstract class PersistentObjectBaseWithNameHierarchical <T> 
{

    private T _Parent;
    virtual public T Parent
    {
        get
        {
            return _Parent;
        }
        set
        {
            _Parent = value;
            UpdatePropertiesInHierachy();
        }
    }

    [ForeignKey("Parent")]
    private ICustomList<T> _ChildList = new CustomList<T>();
    virtual public ICustomList<T> ChildList
    {
        get
        {
            return _ChildList;
        }
        set
        {
            _ChildList = value;
            UpdatePropertiesInHierachy();
        }
    }

Answer 3

可能它必须像这样吗？

    public abstract class PersistentObjectBaseWithNameHierarchical<T> : PersistentObjectBaseWithName where T : PersistentObjectBaseWithNameHierarchical<T>
{

    private PersistentObjectBaseWithNameHierarchical<T> _Parent;
    virtual public PersistentObjectBaseWithNameHierarchical<T> Parent
    {
        get
        {
            return _Parent;
        }
        set
        {
            _Parent = value;
            UpdatePropertiesInHierachy();
        }
    }

    [ForeignKey("Parent")]
    private ICustomList<PersistentObjectBaseWithNameHierarchical<T>> _ChildList = new CustomList<PersistentObjectBaseWithNameHierarchical<T>>();
    virtual public ICustomList<PersistentObjectBaseWithNameHierarchical<T>> ChildList
    {
        get
        {
            return _ChildList;
        }
        set
        {
            _ChildList = value;
            UpdatePropertiesInHierachy();
        }
    }


    public void AddChild(PersistentObjectBaseWithNameHierarchical<T> child)
    {
        if (ChildList.Count() != 0)
            child.OrderPosition = ChildList.Max(e => e.OrderPosition) + 1;

        ChildList.Add(child);
    }

    public void OrderChildList()
    {
        foreach (var e in ChildList)
        {
            e.OrderChildList();
        }
        ChildList.Sort((s1, s2) => s1.OrderPosition.CompareTo(s2.OrderPosition));
    }

    public int Level
    {
        get
        {
            if (Parent != null)
            {
                return Parent.Level + 1;
            }
            else
            {
                return 1;
            }
        }
    }


    private double _OrderPosition;
    virtual public double OrderPosition
    {
        get
        {
            if (_OrderPosition == 0)
            {
                // We use the Id as OrderPosition to keep creation order by default
                _OrderPosition = Id;
            }
            return _OrderPosition;
        }
        set
        {
            _OrderPosition = value;
            Parent?.ChildList.Sort((s1, s2) => s1.OrderPosition.CompareTo(s2.OrderPosition));
            UpdatePropertiesInHierachy();
        }
    }

    public void UpdatePropertiesInHierachy()
    {
        PersistentObjectBaseWithNameHierarchical<T> r = GetRoot(this);
        DuringUpdatePropertiesInHierachy();
    }

因为否则我在这里收到错误：

GetRoot（本）

讲

参数1：无法从'HostSystems.Models.PersistentObjectBaseWithNameHierarchical'转换为'T'

感谢您提供进一步的建议！

此致 Fabianus

分层结构化的通用抽象类

3 个答案: