看了几个工厂模式的例子，自己试着写了个，都不知道算不算是，呵呵

用户类------------------------------------------------------------------

class UserInfo
    {
        private int id;

        public int Id
        {
            get { return id; }
            set { id = value; }
        }
        private string name;

        public string Name
        {
            get { return name; }
            set { name = value; }
        }
        private string password;

        public string Password
        {
            get { return password; }
            set { password = value; }
        }
    }

用户管理接口-----------------------------------------------------------

interface UserInfoManage
    {
        string AddUser(UserInfo user);
        string DeleteUser(UserInfo user);
    }

管理员------------------------------------------------------------------

 class AdminUser:UserInfoManage
    {
        #region UserInfoManage 成员

        public string AddUser(UserInfo user)
        {
            return "添加管理员成功";
        }

        public string DeleteUser(UserInfo user)
        {
            return "删除管理员成功";
        }

        #endregion
    }

普通用户----------------------------------------------------------

 class CommonUser:UserInfoManage
    {
        #region UserInfoManage 成员

        public string AddUser(UserInfo user)
        {
            return "添加普通用户成功";
        }

        public string DeleteUser(UserInfo user)
        {
            return "删除普通用户成功";
        }
      
        #endregion
    }

用户类型的枚举--------------------------------------------------------------------

　enum UserType{CommonUser,AdminUser};

工厂类-----------------------------------------------------------------------------

    class UserInfoFactory
    {
        private static UserInfoManage user;
        public static UserInfoManage NewInstance(UserType type)
        {
            switch (type)
            {
                case UserType.CommonUser:
                    user = new CommonUser();
                    break;
                case UserType.AdminUser:
                    user = new AdminUser();
                    break;
                default:
                    user = null;
                    break;
            }
            return user;
        }
    }

程序调用----------------------------------------------------------------------------------------

UserInfoManage user = UserInfoFactory.NewInstance(UserType.CommonUser);

MessageBox.Show(user.AddUser());

看网上说的意思貌似我的只是简单工厂，但我看抽象工厂除了复杂一些以外没什么，主要还是不知道怎么用，就是不知道好在哪儿，呵呵，有高手的话还望指点指点，给个有意义的小例子