public People(Cat c)
{
c.Cry += new Cat.Crying(c_Cry);//注册了猫叫事件，人听到猫叫则惊醒
}
/// <summary>
/// 注册.
/// </summary>
/// <param name="c">The c.</param>
public Mouse(Cat c)
{
c.Cry += new Cat.Crying(C_Cry); //注册了猫叫事件，老鼠听到猫叫则逃跑
}
