C#设计模式06——适配器的写法

目标角色

    public interface IHelper
    {
        void Add<T>();
        void Delete<T>();
        void Update<T>();
        void Query<T>();
    }

被适配器角色

sqlserver、mysql、redis

 适配器角色

SqlServerHelper

    public class SqlServerHelper : IHelper
    {
        public void Add<T>()
        {
            Console.WriteLine("This is {0} Add", this.GetType().Name);
        }
        public void Delete<T>()
        {
            Console.WriteLine("This is {0} Delete", this.GetType().Name);
        }
        public void Update<T>()
        {
            Console.WriteLine("This is {0} Update", this.GetType().Name);
        }
        public void Query<T>()
        {
            Console.WriteLine("This is {0} Query", this.GetType().Name);
        }
    }

MysqlHelper

    public class MysqlHelper : IHelper
    {
        public void Add<T>()
        {
            Console.WriteLine("This is {0} Add", this.GetType().Name);
        }
        public void Delete<T>()
        {
            Console.WriteLine("This is {0} Delete", this.GetType().Name);
        }
        public void Update<T>()
        {
            Console.WriteLine("This is {0} Update", this.GetType().Name);
        }
        public void Query<T>()
        {
            Console.WriteLine("This is {0} Query", this.GetType().Name);
        }
    }

对于一些第三方的组件方法，它里面已有类似的方法，这个时候我们可以采取 继承或 组合的方式，来做适配

    /// <summary>
    /// 第三方提供的  openstack  servicestack
    /// 不能修改
    /// </summary>
    public class RedisHelper
    {
        public RedisHelper()
        {
            Console.WriteLine($"构造RedisHelper");
        }
        public void AddRedis<T>()
        {
            Console.WriteLine("This is {0} Add", this.GetType().Name);
        }
        public void DeleteRedis<T>()
        {
            Console.WriteLine("This is {0} Delete", this.GetType().Name);
        }
        public void UpdateRedis<T>()
        {
            Console.WriteLine("This is {0} Update", this.GetType().Name);
        }
        public void QueryRedis<T>()
        {
            Console.WriteLine("This is {0} Query", this.GetType().Name);
        }
    }

类适配器，通过继承的方式，在它上面实现目标IHelper

    /// <summary>
    /// 类适配器
    /// </summary>
    public class RedisHelperInherit : RedisHelper, IHelper
    {
        public RedisHelperInherit()
        {
            Console.WriteLine($"构造{this.GetType().Name}");
        }

        public void Add<T>()
        {
            base.AddRedis<T>();
        }

        public void Delete<T>()
        {
            base.DeleteRedis<T>();
        }

        public void Query<T>()
        {
            base.QueryRedis<T>();
        }

        public void Update<T>()
        {
            base.UpdateRedis<T>();
        }
    }

对象适配器，通过组合的方式，在它上面实现目标IHelper

    public class RedisHelperObject : IHelper
    {
        public RedisHelperObject()
        {
            Console.WriteLine($"构造{this.GetType().Name}");
        }
        //属性注入 声明写死
        private RedisHelper _RedisHelper = new RedisHelper();

        ////构造函数 可以替换(需要抽象) 
        public RedisHelperObject(RedisHelper redisHelper)
        {
            this._RedisHelper = redisHelper;
        }

        ////方法注入 可以替换(需要抽象)
        public void SetObject(RedisHelper redisHelper)
        {
            this._RedisHelper = redisHelper;
        }

        public void Add<T>()
        {
            this._RedisHelper.AddRedis<T>();
        }

        public void Delete<T>()
        {
            this._RedisHelper.DeleteRedis<T>();
        }

        public void Query<T>()
        {
            this._RedisHelper.QueryRedis<T>();
        }

        public void Update<T>()
        {
            this._RedisHelper.UpdateRedis<T>();
        }
    }

运行测试

            {
                //继承 既满足现有的规范调用，又没有修改RedisHelper  
                //类适配器模式
                IHelper helper = new RedisHelperInherit();
                helper.Add<Program>();
                helper.Delete<Program>();
                helper.Update<Program>();
                helper.Query<Program>();
            }
            {
                //组合 既满足现有的规范调用，又没有修改RedisHelper 
                //对象适配器
                IHelper helper = new RedisHelperObject();
                helper.Add<Program>();
                helper.Delete<Program>();
                helper.Update<Program>();
                helper.Query<Program>();
            }