Point的属性在.net中

Question

你们觉得哪些更好？

private Point location;

public int LocationX { get { return location.X; } }
public int LocationY { get { return location.Y; } }

要么

private Point location;

public Point Location { get { return location; } }

第二种方法的问题在于,X并且Y可以通过类的客户端进行突变,在这种情况下,客户端不是我想要的.我应该做一个包装,Point所以我可以返回一个不可变的Point？

谢谢

Answer 1

我更喜欢第二种方法,因为X和Y成员不可变(Point是结构,因此是值类型).也就是说,您无法更改位置,因为您无法修改类的Location属性的X或Y属性,因为Point是值成员.如果要更改它,则必须实例化一个新的Point实例.

请看下面的示例,编译器将阻止您更改Location属性的X或Y成员:

class Program
{
    private class MyType
    {
        private readonly Point _location;

        public MyType(Point location)
        {
            _location = location;
        }

        public Point Location
        {
            get
            {
                return _location;
            }
        }
    }

    static void Main( string[] args )
    {
        var someInstance = new MyType (new Point (5, 6));

        someInstance.Location.X = 5; // <- compiler error: cannot modify the expression because it is not a variable.
    }