就不能换DB吗？ 抽象工厂模式

15.1 就不能换DB吗？

15.2 最基本的数据访问程序

namespace 抽象工厂模式
{
    class Program
    {
        static void Main(string[] args)
        {
            User user = new User();

            SqlserverUser su = new SqlserverUser();   //与SQLServer耦合，

            su.Insert(user);
            su.GetUser(1);

            Console.Read();
        }
    }

    //用户类，
    class User
    {
        private int _id;

        public int ID
        {
            get { return _id; }
            set { _id = value; }
        }

        private string _name;

        public string Name
        {
            get { return _name; }
            set { _name = value; }
        }
    }

    //操作User表类，
    class SqlserverUser
    {
        //新增用户，
        public void Insert(User user)
        {
            Console.WriteLine("在Sqlserver中给User表增加一条记录");
        }

        //得到用户，
        public User GetUser(int id)
        {
            Console.WriteLine("在Sqlserver中根据ID得到User表一条记录");
            return null;
        }
    }

}

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15.3 用了工厂方法模式的数据访问程序

namespace 抽象工厂模式
{
    class Program
    {
        static void Main(string[] args)
        {
            User user = new User();

            //IFactory factory = new SqlServerFactory();
            IFactory factory = new AccessFactory();

            IUser iu = factory.CreateUser();

            iu.Insert(user);
            iu.GetUser(1);

            Console.Read();
        }
    }

    class User
    {
        private int _id;

        public int ID
        {
            get { return _id; }
            set { _id = value; }
        }

        private string _name;

        public string Name
        {
            get { return _name; }
            set { _name = value; }
        }
    }

    //IUser接口，用于客户端访问，解除与具体数据库的耦合，
    interface IUser
    {
        void Insert(User user);

        User GetUser(int id);
    }

    //SqlserverUser类，用于访问SQLServer的User，
    class SqlserverUser : IUser
    {
        public void Insert(User user)
        {
            Console.WriteLine("在Sqlserver中给User表增加一条记录");
        }

        public User GetUser(int id)
        {
            Console.WriteLine("在Sqlserver中根据ID得到User表一条记录");
            return null;
        }
    }

    //AccessUser类，用于访问Access的User，
    class AccessUser : IUser
    {
        public void Insert(User user)
        {
            Console.WriteLine("在Access中给User表增加一条记录");
        }

        public User GetUser(int id)
        {
            Console.WriteLine("在Access中根据ID得到User表一条记录");
            return null;
        }
    }

    //IFactory接口，定义一个创建访问User表对象的抽象的工厂接口，
    interface IFactory
    {
        IUser CreateUser();
    }

    //SqlServerFactory类，实现IFactory接口，实例化SqlserverUser，
    class SqlServerFactory : IFactory
    {
        public IUser CreateUser()
        {
            return new SqlserverUser();
        }
    }

    //AccessFactory类，实现IFactory接口，实例化AccessUser，
    class AccessFactory : IFactory
    {
        public IUser CreateUser()
        {
            return new AccessUser();
        }
    }

}

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15.4 用了抽象工厂模式的数据访问程序

namespace 抽象工厂模式
{
    class Program
    {
        static void Main(string[] args)
        {
            User user = new User();
            Department dept = new Department();

            //IFactory factory = new SqlServerFactory();
            IFactory factory = new AccessFactory();

            IUser iu = factory.CreateUser();
            iu.Insert(user);
            iu.GetUser(1);

            IDepartment id = factory.CreateDepartment();
            id.Insert(dept);
            id.GetDepartment(1);

            Console.Read();
        }
    }

    class User
    {
        private int _id;

        public int ID
        {
            get { return _id; }
            set { _id = value; }
        }

        private string _name;

        public string Name
        {
            get { return _name; }
            set { _name = value; }
        }
    }

    class Department
    {
        private int _id;

        public int ID
        {
            get { return _id; }
            set { _id = value; }
        }

        private string _deptName;

        public string DeptName
        {
            get { return _deptName; }
            set { _deptName = value; }
        }
    }

    interface IUser
    {
        void Insert(User user);

        User GetUser(int id);
    }

    class SqlserverUser : IUser
    {
        public void Insert(User user)
        {
            Console.WriteLine("在Sqlserver中给User表增加一条记录");
        }

        public User GetUser(int id)
        {
            Console.WriteLine("在Sqlserver中根据ID得到User表一条记录");
            return null;
        }
    }

    class AccessUser : IUser
    {
        public void Insert(User user)
        {
            Console.WriteLine("在Access中给User表增加一条记录");
        }

        public User GetUser(int id)
        {
            Console.WriteLine("在Access中根据ID得到User表一条记录");
            return null;
        }
    }

    interface IDepartment
    {
        void Insert(Department department);

        Department GetDepartment(int id);
    }

    class SqlserverDepartment : IDepartment
    {
        public void Insert(Department department)
        {
            Console.WriteLine("在Sqlserver中给Department表增加一条记录");
        }

        public Department GetDepartment(int id)
        {
            Console.WriteLine("在Sqlserver中根据ID得到Department表一条记录");
            return null;
        }
    }

    class AccessDepartment : IDepartment
    {
        public void Insert(Department department)
        {
            Console.WriteLine("在Access中给Department表增加一条记录");
        }

        public Department GetDepartment(int id)
        {
            Console.WriteLine("在Access中根据ID得到Department表一条记录");
            return null;
        }
    }

    interface IFactory
    {
        IUser CreateUser();

        IDepartment CreateDepartment();
    }

    class SqlServerFactory : IFactory
    {
        public IUser CreateUser()
        {
            return new SqlserverUser();
        }

        public IDepartment CreateDepartment()
        {
            return new SqlserverDepartment();
        }
    }

    class AccessFactory : IFactory
    {
        public IUser CreateUser()
        {
            return new AccessUser();
        }

        public IDepartment CreateDepartment()
        {
            return new AccessDepartment();
        }
    }

}

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15.5 抽象工厂模式

提供一个创建一系列相关或相互依赖对象的接口，而无需指定它们具体的类，

15.6 抽象工厂模式的优点与缺点

15.7 用简单工厂来改进抽象工厂

15.8 用反射+抽象工厂的数据访问程序

15.9 用反射+配置文件的数据访问程序

15.10 无痴迷 不成功