Question

示例：

public class BoundingBox
{
    public Vector3Double Positon { get; set; }
    public Vector3Double Apothem { get; set; }
    public ExtremasForX X;

    public BoundingBox(Vector3Double position, Vector3Double size)
    {
        Positon = position;
        X = new ExtremasForX(this);

    }

    private class ExtremasForX
    {
        private BoundingBox box;
        public ExtremasForX(BoundingBox box)
        {
            this.box = box;
        }
        public double Max
        {   
            get { return box.Positon.X + box.Apothem.X ; }
        }
        public double Min
        {
            get { return box.Positon.X - box.Apothem.X; }
        }



    }
}

此代码产生可访问性错误：BoundingBox.X的级别高于其类型。

我想要一个没有公共构造函数的内部类，因为我只希望将该类用作外部类的命名空间。我该怎么办？

Answer 1

如果确实不希望公开内部类型，则可以让内部类实现接口。然后，在外部类中，将X公开为接口类型，但在内部使用内部类的类型。

就个人而言，我只是将内部类公开。用户不能通过实例化类来伤害任何东西，因此暴露构造函数并不是什么大事。

通过接口公开内部类型而不暴露构造函数的代码：

public class BoundingBox
{
    public Vector3Double Positon { get; set; }
    public Vector3Double Apothem { get; set; }
    public IExtremasForX X { get { return _x; } }
    private ExtremasForX _x;

    public BoundingBox(Vector3Double position, Vector3Double size)
    {
        Positon = position;
        _x = new ExtremasForX(this);
    }
    public interface IExtremasForX {
        public double Max { get; }
        public double Min { get; }
    }

    private class ExtremasForX : IExtremasForX
    {
        private BoundingBox box;
        public ExtremasForX(BoundingBox box)
        {
            this.box = box;
        }
        public double Max
        {   
            get { return box.Positon.X + box.Apothem.X ; }
        }
        public double Min
        {
            get { return box.Positon.X - box.Apothem.X; }
        }
    }
}

Answer 2

将class ExtremasForX的访问修饰符更改为public，并将其构造函数更改为internal而不是public，如下所示：

public class BoundingBox
{
    public Vector3Double Positon { get; set; }
    public Vector3Double Apothem { get; set; }
    public ExtremasForX X;

    public BoundingBox(Vector3Double position, Vector3Double size)
    {
        Positon = position;
        X = new ExtremasForX(this);

    }

    public class ExtremasForX
    {
        private BoundingBox box;
        internal ExtremasForX(BoundingBox box)
        {
            this.box = box;
        }
        public double Max
        {   
            get { return box.Positon.X + box.Apothem.X ; }
        }
        public double Min
        {
            get { return box.Positon.X - box.Apothem.X; }
        }



    }
}

如何创建一个可用作外部类中的公共字段的私有嵌套类？

2 个答案: