c#扩展方法

public class Card
{
    private Chow chow;  //吃牌属性
    private Pong pong;    //碰牌属性
    private Kong kong;  //明杠牌属性
    private UnKong unKong;  //暗杠属性
    private CardCtrl cardCtrl;
    private readonly int weight;       //牌的权值
    private CardType.CharacterType belongto;  //角色类型
/// <summary>
/// 构造一张card
/// </summary>
/// <param name="Weight">哪张牌</param>
/// <param name="Belongto">属于谁</param>
/// <param name="cardCtrl">cardCtrl的引用</param>
    public Card(int Weight,CardType.CharacterType Belongto, CardCtrl cardCtrl)
    {
        weight = Weight;
        belongto = Belongto;
        this.cardCtrl = cardCtrl;
    }

/// <summary>
/// 设置chow，返回chow
/// </summary>
    public Chow Chow
    {
        set { chow = value; }
        get { return chow; }
    }
/// <summary>
/// 设置pong,返回pong
/// </summary>
    public Pong Pong
    {
        set { pong = value; }
        get { return pong; }
    }
    /// <summary>
    /// 设置exposed，返回exposed
    /// </summary>
    public Kong Kong
    {
        set { kong = value; }
        get { return kong; }
    }

   /// <summary>
    /// 设置 CardCtrl 返回CardCtrl
    /// </summary>
    public CardCtrl CardCtrl
    {
       set
       {
         //  GameObject.Destroy(cardCtrl.transform.parent.gameObject);
           cardCtrl = value;
       }
        get { return cardCtrl; }
    }
    /// <summary>
    /// 返回牌的权值
    /// </summary>
    public int  GetCardWeight
    {
        get { return weight; }
    }
    /// <summary>
    /// 牌的归属
    /// </summary>
    public CardType.CharacterType Attribution
    {
        set { belongto = value; }
        get { return belongto; }
    }

}

public static class nnn
{
public static void SayHello(this Card card)
{
Debug.Log("这是一个扩展方法");