接口改变已装箱值类型中的字段.txt

C# 是创新性的新式编程语言

using System;
namespace TestInFace
{
	
	interface IChangeBoxedPoint
	{
		void Change(Int32 x,Int32 y);
	}
	public struct Point:IChangeBoxedPoint
	{
		public Int32 x,y;
		public Point(Int32 x,Int32 y)
		{
			this.x=x;
			this.y=y;
		}
		public void Change(Int32 x,Int32 y)
		{
			this.x=x;
			this.y=y;
		}
		public override String ToString()
		{
			return String.Format("({0},{1})",x,y);
		}
		
	}
	class Class1
	{
		[STAThread]
		static void Main(string[] args)
		{
			Point p=new Point();
			p.x=p.y=1;
			Console.WriteLine(p);

			p.Change(2,2);
			Console.WriteLine(p);

			Object o=p;
			Console.WriteLine(o);

			((Point)o).Change(3,3);//没有达到期望
			Console.WriteLine(o);

			((IChangeBoxedPoint)o).Change(5,5);//达到期望(使用接口改变已装箱值类型中的字段)
			Console.WriteLine(o);

			
		}
	}
}