Question

模型中是否可以有递归属性？目标是使用每个操作动态构建字符串。这是我正在使用的：

public class Action
{
    public int ActionId { get; set; }
    public int? ParentId { get; set; }
    public string Name { get; set; }
    public string ActionName { 
    {
        get
        {
            // example result: 1Ai or 2Bi
            return ....
        }
    }
}

List<Action> aList = new List<Action>() {
    new Action { ActionId = 1, Name = "Step 1" },
    new Action { ActionId = 2, Name = "Step 2" },
    new Action { ActionId = 3, ParentId = 1, Name = "A" },
    new Action { ActionId = 4, ParentId = 1, Name = "B" },
    new Action { ActionId = 5, ParentId = 2, Name = "A" },
    new Action { ActionId = 6, ParentId = 2, Name = "B" },
    new Action { ActionId = 5, ParentId = 3, Name = "i" },
    new Action { ActionId = 6, ParentId = 6, Name = "i" }
}

Answer 1

这当然是可能的（虽然我不会称之为递归）。您可以通过在构造函数中传递父代来完成它。

public class Foo
{
   public Foo(string name)
   {
      Name = name;
   }

   public Foo(Foo parent, string name)
   {
      Name = parent.Name + name;
   }

   public string Name {get; set;}
}

//


var foo = new Foo("Step 1");
var bar = new Foo(foo, "A");

// etc.

有时人们喜欢在子类中保留对整个父类的引用，因此例如可以使用最新版本动态生成name属性。

这确实会产生一连串的调用（所以要小心！）

public class Foo
{
   string _innerName;

   public Foo(string name)
   {
      _innerName = name;
   }

   public Foo(Foo parent, string name)
   {
      _innerName = name;
      _parent = parent;
   }

   public string Name
   {
      get
      {
         return parent == null? _innerName; parent.Name + _innerName;
      }
   }
}

//


var foo = new Foo("Step 1");
var bar = new Foo(foo, "A");

// etc.

Answer 2

有很多方法可以实现，其中一种可能的方法是：

    class Program
    {
        static List<Action> aList;

        static void Main(string[] args)
        {
            aList = new List<Action>() {
    new Action { ActionId = 1, Name = "Step 1" },
    new Action { ActionId = 2, Name = "Step 2" },
    new Action { ActionId = 3, ParentId = 1, Name = "A" },
    new Action { ActionId = 4, ParentId = 1, Name = "B" },
    new Action { ActionId = 5, ParentId = 2, Name = "A" },
    new Action { ActionId = 6, ParentId = 2, Name = "B" },
    new Action { ActionId = 5, ParentId = 3, Name = "i" },
    new Action { ActionId = 6, ParentId = 6, Name = "i" }
};
            Console.WriteLine(aList[2].ActionName);
            Console.ReadKey();

        }

        public class Action
        {
            public int ActionId { get; set; }
            public int? ParentId { get; set; }
            public string Name { get; set; }
            public string ActionName
            {

                get
                {
                    // example result: 1Ai or 2Bi
                    var parent = aList.Find((p) => p.ActionId == ParentId).ActionId;
                    var child = aList.Find((p) => p.ParentId == ActionId).Name;
                    return  String.Format("{0}{1}{2}", parent, Name, child) ;
                }
            }
        }
    }

模型中的递归属性

2 个答案: