如何用一些进程在动态参数内创建对象？

Posted 2021-04-15

当我从MyMenu类创建对象时，我遇到了几个错误

我希望在ctor中

• Id参数将自动增加
• 当我创建对象时，它应该添加到MyMenuList

你介意告诉我正确的方法吗？

My menu class properties

public abstract class MenuProperties
{
    public byte Id { get; }
    public string MenuName { get; set; }
    public bool IsSubMenu { get; set; }
    public abstract void AddMenu(MyMenu menu);
    public abstract void DeleteMenu(MyMenu menu);
    public List<MyMenu> MyMenuList { get; set; }
}
public class MyMenu : MenuProperties
{
    public MyMenu()
    {
       Id++; //it's always 0
       MyMenuList.Add(this); // How to fix here, stackoverflow error when I run it
    }

    public override void AddMenu(MyMenu menu)
    {
        MyMenuList.Add(menu); 
    }

    public override void DeleteMenu(MyMenu menu)
    {
        MyMenuList.Remove(menu);
    }

    public override string ToString()
    {
        return base.Id.ToString() + " " + MenuName.ToString();
    }
}

---

How I am using it

    static void Main(string[] args)
    {
        MyMenu menu = new MyMenu
        {
            Id = 0,
            IsSubMenu = false,
            MenuName = "Default",
        };
        MyMenu menu1 = new MyMenu
        {
            Id = 1,
            IsSubMenu = false,
            MenuName = "Home",
        };
        MyMenu menu2 = new MyMenu
        {
            Id = 2,
            IsSubMenu = false,
            MenuName = "Settings",
        };
        MyMenu menu3 = new MyMenu
        {
            Id = 3,
            IsSubMenu = true,
            MenuName = "Add Menu",
        };
        MyMenu menu4 = new MyMenu
        {
            Id = 4,
            IsSubMenu = true,
            MenuName = "Remove Menu",
        };
        menu.AddMenu(menu);// I wanna just remove this methods
        menu1.AddMenu(menu1);// But When I create object from MyMenu class
        menu2.AddMenu(menu2);// I wanna add this object to any list when 
        menu3.AddMenu(menu3);// its created.
        menu4.AddMenu(menu4);// I am thinking, it can be in ctor
        //But I am taking error.
        Console.ReadLine();
    }

可能有很多逻辑错误bcs我是新手。但是，当我看到负面投票。它让我很伤心。顺便说一下，我说我的语言是如此之低。

答案

你的MyMenuList和一个计数器应该是MyMenu类的静态成员。我不知道你会用什么MyMenuList列表，这样就没有任何意义。每个实例在其列表中只有一个项目;本身。此外，引用抽象类的子类型没有意义。你应该有一个MenuProperties而不是MyMenu的列表。如果我错了，请纠正我。

public abstract class MenuProperties
{
    private static byte LastId = 0;
    public static List<MenuProperties> MyMenuList { get; } = new List<MenuProperties>();

    public byte Id { get; }
    public string MenuName { get; set; }
    public bool IsSubMenu { get; set; }

    protected MenuProperties()
    {
        Id = LastId++;
    }

    public abstract void AddMenu(MenuProperties menu);
    public abstract void DeleteMenu(MenuProperties menu);
}
public class MyMenu : MenuProperties
{
    public MyMenu()
    {
        //This was not a Stack overflow, the MyMenuList was null; you didn't initialise it.
        MyMenuList.Add(this);
    }

    public override void AddMenu(MenuProperties menu)
    {
        MyMenuList.Add(menu);
    }

    public override void DeleteMenu(MenuProperties menu)
    {
        MyMenuList.Remove(menu);
    }

    public override string ToString()
    {
        return Id.ToString() + " " + MenuName;
    }
}