三层架构之泛型抽象

Posted 2021-02-14 xuan666

关于泛型抽象工厂，最近自己写了一个项目，现在拿出来和大家分享，有助于我们学习。

项目截图如下：

XU.Model层中有一个抽象类BaseModel.cs是用户实体类，继承与BaseModel类，是用于类型安全考虑的,从而让 各实体类有一个统一的父类，在其他层使用的时候，可以使用里氏替换原则的考虑。

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace XU.Model
 8 {
 9     /// <summary>
10     /// 该抽象类为所有实体类的父类
11     /// 所有实体类继承该抽象类，为保持类型一致而设计的父类，也是出于安全性的考虑
12     /// </summary>
13     public abstract class BaseModel
14     {
15 
16     }
17 }

BaseModel.cs

 1  1 using System;
 2  2 using System.Collections.Generic;
 3  3 using System.Linq;
 4  4 using System.Text;
 5  5 using System.Threading.Tasks;
 6  6 
 7  7 namespace XU.Model.Student
 8  8 {
 9  9     /// <summary>
10 10     /// 实体类Student继承自BaseModel
11 11     /// 调用时就可以通过BaseModel model=new Student();
12 12     /// </summary>
13 13     public class Student : BaseModel
14 14     {
15 15         public int Id { get; set; }
16 16         public string Name { get; set; }
17 17         public string SubjectName { get; set; }
18 18         public int Score { get; set; }
19 19     }
20 20 }

Student.cs

XU.FactoryDAL层是用于反射获取实例，其中只用一个类。

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace XU.FactoryDAL
 8 {
 9     public class DataAccess<T> where T : class
10     {
11         //获取配置路径
12         private static readonly string path = System.Configuration.ConfigurationManager.AppSettings["DAL"];
13         private DataAccess() { }
14         /// <summary>
15         /// 创建实例  反射创建实例
16         /// </summary>
17         /// <param name="Type"></param>
18         /// <returns></returns>
19         public static T CreateDAL(string Type)
20         {
21             string className = string.Format(path + ".{0}", Type);
22             try
23             {
24                 return (T)System.Reflection.Assembly.Load(path).CreateInstance(className);
25             }
26             catch (Exception ex)
27             {
28 
29                 throw new Exception(ex.Message.ToString());
30             }
31         }
32     }
33 }

DataAccess.cs

XU.IDAL层依赖与XU.Model，其中包含一个基类接口IBaseDal.cs,还有一个用于定义一些基类接口没有方法的接口IStudentDal.cs,继承接口IBaseDal<T>。

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace XU.IDAL
 8 {
 9     /// <summary>
10     /// 所有的dal基本都有增删改查等功能，提取到dal接口层
11     /// 所有实现该接口的类必须实现所有的未实现的成员
12     /// </summary>
13     /// <typeparam name="T"></typeparam>
14     public interface IBaseDal<T> where T:XU.Model.BaseModel,new()
15     {
16         int Add(T model);
17         int Delete(int Id);
18         int Update(T model);
19         T GetModel(int Id);
20     }
21 }

IBaseDal.cs

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace XU.IDAL
 8 {
 9     /// <summary>
10     /// 需有特殊的方法的  可定义子接口
11     /// 如：登录   判断用户名是否存在
12     /// </summary>
13     public interface IStudentDal:IBaseDal<Model.Student.Student>
14     {
15 
16         /// <summary>
17         /// 判断用户名是否存在
18         /// </summary>
19         /// <param name="userName"></param>
20         /// <returns></returns>
21         // bool Exists(string userName);
22         /// <summary>
23         /// 登录
24         /// </summary>
25         /// <param name="name"></param>
26         /// <param name="pwd"></param>
27         /// <returns></returns>
28         // Model.UserModel Login(string name, string pwd);
29 
30         //显示方法可写到IBaseDal.cs 不属于特殊方法
31         List<Model.Student.Student> GetList(); 
32         
33     }
34 }

IStudentDal.cs

实现XU.IDAL中接口有2个类库，一个是MSSQL类库，一个是mysql类库，这2两个类库都依赖于XU.Model和XU.IDAL,下面是实现方法。

XU.MSSQLDAL的实现方法如下：

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Data;
 4 using System.Linq;
 5 using System.Text;
 6 using System.Threading.Tasks;
 7 using XU.Model.Student;
 8 
 9 namespace XU.MSSQDAL
10 {
11     public class StudentDal : IDAL.IStudentDal
12     {
13         /// <summary>
14         /// 添加
15         /// </summary>
16         /// <param name="model"></param>
17         /// <returns></returns>
18         public int Add(Student model)
19         {
20             string sql = string.Format("insert into Student values(‘{0}‘,‘{1}‘,{2})", model.Name, model.SubjectName, model.Score);
21             return DBHelper.ExecuteNonQuery(sql);
22         }
23         /// <summary>
24         /// 删除
25         /// </summary>
26         /// <param name="Id"></param>
27         /// <returns></returns>
28         public int Delete(int Id)
29         {
30             string sql = "Delete Student where Id=" + Id;
31             return DBHelper.ExecuteNonQuery(sql);
32         }
33         /// <summary>
34         /// 查询显示
35         /// </summary>
36         /// <returns></returns>
37         public List<Student> GetList()
38         {
39             string sql = "select * from Student";
40             return DBHelper.GetList<Student>(sql);
41         }
42         /// <summary>
43         /// 反填
44         /// </summary>
45         /// <param name="Id"></param>
46         /// <returns></returns>
47         public Student  GetModel(int Id)
48         {
49             string sql = "select * from Student where Id=" + Id;
50             return DBHelper.GetList<Student>(sql).FirstOrDefault();
51         }
52         /// <summary>
53         /// 修改
54         /// </summary>
55         /// <param name="model"></param>
56         /// <returns></returns>
57         public int Update(Student model)
58         {
59             string sql = string.Format("Update Student Set Name=‘{0}‘,SubjectName=‘{1}‘,Score={2} where Id={3}",model.Name,model.SubjectName,model.Score,model.Id);
60             return DBHelper.ExecuteNonQuery(sql);
61         }
62     }
63 }

StudentDal.cs

XU.MYSQLDAL的实现方法如下：

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Data;
 4 using System.Linq;
 5 using System.Text;
 6 using System.Threading.Tasks;
 7 using XU.Model.Student;
 8 
 9 namespace XU.MYSQLDAL
10 {
11     public class StudentDal : IDAL.IStudentDal
12     {
13         /// <summary>
14         /// 添加
15         /// </summary>
16         /// <param name="model"></param>
17         /// <returns></returns>
18         public int Add(Student model)
19         {
20             string sql = string.Format("insert into Student(Name,SubjectName,Score) values(‘{0}‘,‘{1}‘,{2})", model.Name, model.SubjectName, model.Score);
21             return MySqlDBHelper.ExecuteNonQuery(sql);
22         }
23         /// <summary>
24         /// 删除
25         /// </summary>
26         /// <param name="Id"></param>
27         /// <returns></returns>
28         public int Delete(int Id)
29         {
30             string sql = "Delete from Student where Id=" + Id;
31             return MySqlDBHelper.ExecuteNonQuery(sql);
32         }
33         /// <summary>
34         /// 查询显示
35         /// </summary>
36         /// <returns></returns>
37         public List<Student>  GetList()
38         {
39             string sql = "select * from Student";
40             return MySqlDBHelper.GetList<Student>(sql);
41         }
42         /// <summary>
43         /// 反填
44         /// </summary>
45         /// <param name="Id"></param>
46         /// <returns></returns>
47         public Student GetModel(int Id)
48         {
49             string sql = "select * from Student where Id=" + Id;
50             return MySqlDBHelper.GetList<Student>(sql).FirstOrDefault();
51         }
52 
53         public int Update(Student model)
54         {
55             string sql = string.Format("update Student set Name=‘{0}‘,SubjectName=‘{1}‘,Score=‘{2}‘  where  Id ={3}", model.Name, model.SubjectName, model.Score, model.Id);
56             return MySqlDBHelper.ExecuteNonQuery(sql);
57         }
58 
59        
60 
61     }
62 }

StudentDal.cs

XU.BLL业务逻辑层中包含了一个用于继承的基类BaseBLL<T>和用户业务逻辑StudentBll类，这层依赖XU.IDAL,XU.Model,XU.FactoryDAL库

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace XU.BLL
 8 {
 9     public class BaseBLL<T> where T:XU.Model.BaseModel,new()
10     {
11         protected XU.IDAL.IBaseDal<T> Dal;
12         public BaseBLL(string type)
13         {
14             //通过工厂得到dal
15             Dal = XU.FactoryDAL.DataAccess<XU.IDAL.IBaseDal<T>>.CreateDAL(type);
16         }
17         /// <summary>
18         /// 增加
19         /// </summary>
20         /// <param name="model"></param>
21         /// <returns></returns>
22         public virtual int Add(T model)
23         {
24             return Dal.Add(model);
25         }
26         /// <summary>
27         /// 删除
28         /// </summary>
29         /// <param name="Id"></param>
30         /// <returns></returns>
31         public virtual int Delete(int Id)
32         {
33             return Dal.Delete(Id);
34         }
35         /// <summary>
36         /// 修改
37         /// </summary>
38         /// <param name="model"></param>
39         /// <returns></returns>
40         public virtual int Update(T model)
41         {
42             return Dal.Update(model);
43         }
44         /// <summary>
45         /// 反填
46         /// </summary>
47         /// <param name="Id"></param>
48         /// <returns></returns>
49         public virtual T GetModel(int Id)
50         {
51             return Dal.GetModel(Id);
52         }
53     }
54 }

BaseBLL.cs

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Data;
 4 using System.Linq;
 5 using System.Text;
 6 using System.Threading.Tasks;
 7 using XU.Model.Student;
 8 
 9 namespace XU.BLL
10 {
11     public class StudentBll:BaseBLL<XU.Model.Student.Student>
12     {
13         private const string _Type = "StudentDal";
14         private XU.IDAL.IStudentDal _Dal;
15         public StudentBll() : base(_Type)
16         {
17             _Dal = base.Dal as XU.IDAL.IStudentDal;
18             if(_Dal == null)
19             {
20                 throw new NullReferenceException(_Type);
21             }
22         }
23         /// <summary>
24         /// 查询方法
25         /// </summary>
26         /// <returns></returns>
27         public List<Student> GetList()
28         {
29             return _Dal.GetList();
30         }
31     }
32 }

StudentBll.cs

XU.ConsoleDemo是一个MVC项目，用这个讲解抽象工厂更简单和直观，项目中只包含了基础的增删改查操作

控制器如下：

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Web;
 5 using System.Web.Mvc;
 6 using XU.BLL;
 7 using XU.Model.Student;
 8 using Newtonsoft.Json;
 9 using System.Data;
10 
11 namespace XU.ConsoleDemo.Controllers
12 {
13     public class SchoolController : Controller
14     {
15         StudentBll bll = new StudentBll();
16         /// <summary>
17         /// 添加显示方法
18         /// </summary>
19         /// <returns></returns>
20         [HttpGet]
21         public ActionResult Create()
22         {
23             return View();
24         }
25         /// <summary>
26         /// 添加执行方法
27         /// </summary>
28         /// <param name="stu"></param>
29         /// <returns></returns>
30         [HttpPost]
31         public ActionResult Create(Student stu)
32         {
33             int n = bll.Add(stu);
34             if (n > 0)
35             {
36                 return Content("添加成功");
37             }
38             else
39             {
40                 return Content("添加失败");
41             }
42         }
43         /// <summary>
44         /// 学生显示
45         /// </summary>
46         /// <returns></returns>
47         public ActionResult Index()
48         {
49             var list =  bll.GetList();
50             var json = JsonConvert.SerializeObject(list);
51             List<Student> show = JsonConvert.DeserializeObject<List<Student>>(json);
52             return View(show);
53         }
54         public ActionResult Delete(int Id)
55         {
56             int n = bll.Delete(Id);
57             if (n > 0)
58             {
59                 return Content("删除成功");
60             }
61             else
62             {
63                 return Content("删除失败");
64             }
65         }
66         /// <summary>
67         /// 修改反填
68         /// </summary>
69         /// <param name="Id"></param>
70         /// <returns></returns>
71         [HttpGet]
72         public ActionResult Edit(int Id)
73         {
74            Student stu =  bll.GetModel(Id);
75           
76             return View(stu);
77         }
78         /// <summary>
79         /// 修改执行方法
80         /// </summary>
81         /// <param name="stu"></param>
82         /// <returns></returns>
83         [HttpPost]
84         public ActionResult Edit(Student stu)
85         {
86             int n = bll.Update(stu);
87             if (n > 0)
88             {
89                 return Content("修改成功");
90             }
91             else
92             {
93                 return Content("修改失败");
94             }
95         }
96 
97     }
98 }

SchoolController.cs

 

web.config程序集名称

 1 <?xml version="1.0" encoding="utf-8" ?>
 2 <configuration>
 3   <appSettings>
 4     <!--DAL路径-->
 5     <add key="DAL" value="XU.MYSQLDAL"/>
 6       <!--
 7         <add key="DAL" value="XU.MSSQDAL"/>
 8         -->
 9   </appSettings>
10 </configuration>

Web.config

 

注意：XU.ConsoleDemo是不会直接引用XU.MSSQLDAL和XU.MYSQLDAL的，但是XU.ConsoleDemo中的Debug目录下要把编译好的XU.MSSQLDAL.dll和XU.MYSQLDAL.dll放进去，如果是网站就要放入网站中的Bin文件夹下

 源码下载: https://pan.baidu.com/s/1CsbkCQl2M8IQ7BEtVMLKng 提取码: 5w36