如下程序片段
using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
namespace ConsoleApplication1
{
    class PersonComparName:IComparer
    {
        public static IComparer Default = new PersonComparName();
        public int Compare(object x, object y)
        {
            if ((x is Person) && (y is Person))
            {
                return Comparer.Default.Compare(
                    ((Person)x).Name, ((Person)y).Name);
            }
            else
            {
                throw new ArgumentException("one or both object to compare are not Person object.");
            }
        }
    }
}
不是说接口不能进行实例化吗?
还有定义迭代器时:
public static IEnumaerable List()
{
    yield return (.......);
}
既然不能实例化,怎么等定义变量,怎么能作为函数返回类型的?
困惑 .....
.....
待高手讲解....

 
											





