ASP.NET Core：使用Dapper和SwaggerUI来丰富你的系统框架

一、概述

1、用VS2017创建如下图的几个.NET Standard类库，默认版本为1.4，你可以通过项目属性进行修改，最高支持到1.6，大概五月份左右会更新至2.0，API会翻倍，很期待！

排名分先后，这里简要说下我对各个类库职责的一个理解。 Light.Model：存放实际项目中你用到的所有实体集合，包括数据库表映射实体，请求实体，响应实体，视图显示实体以及一些公共实体类等，同时你还可以根据自己业务的模块功能进行更细致的划分。 Light.IRepository：数据库仓储接口，定义你操作数据库的所有动作，包括简单的C（Create）R（Retrive）U（Update）D（Delete），也就是我们经常说的增查改删。对于上层服务而言，我只要暴露出来操作数据库的接口就可以了，而不需要关注具体的实现，这样一来，不管我使用Dapper还是EF Core，抑或是SQLServer或者MySql，对调用者来说，不会有任何影响。 Light.Repository：各种请求数据库数据的方法都在这里，你可以选择自己喜欢的工具，自己喜欢的语言来丰富它，sql也好，linq也罢，只要你高兴，随时可以搞起来。 Light.IBusiness和Light.Business：业务逻辑接口定义和实现，理解了上面说的, 这两层其实含义是差不多的。复杂的业务逻辑，验证或者判断等等，你都在Business里边实现好，至于以后是web api来调用还是普通的web来调用，这些都交由IBusiness来做就可以了 Light.DependencyInjection：依赖注入。从此解放我们的双手，再也不用new来new去了，代码也整洁了，同时也解耦了，况且它已经被集成到.net core中，何乐而不为呢。 那么剩下如果后续有需要Common层或者Web层的，向解决方案里边添加就好，这俩就不用过多解释什么了，你懂的

2、当然了，你还可以通过.NET Core Tool的cli命令来创建，前提是你的电脑上安装了.NET Core SDK。

dotnet new classlib -n Light.Repository //创建一个名字为Light.Repository的.NET Standard类库

更多创建类型请键入如下命令进行查看

dotnet new -all

红框内自上而下依次表示：

• 控制台应用程序
• 类库
• 微软自带的单元测试项目
• 引入XUnit框架的单元测试项目
• 空的ASP.NET Core
• ASP.NET Core MVC项目
• ASP.NET Core WebAPI项目
• 空的解决方案

二、引入Dapper

1、准备创建用户表的SQL脚本

 1 USE [Light]
 2 GO
 3 
 4 /****** Object:  Table [dbo].[User]    Script Date: 2017/3/27 22:40:08 ******/
 5 SET ANSI_NULLS ON
 6 GO
 7 
 8 SET QUOTED_IDENTIFIER ON
 9 GO
10 
11 CREATE TABLE [dbo].[User](
12     [Id] [int] IDENTITY(10000,1) NOT NULL,
13     [UserName] [nvarchar](50) NOT NULL,
14     [Password] [nvarchar](50) NOT NULL,
15     [Gender] [bit] NOT NULL,
16     [Birthday] [datetime] NOT NULL,
17     [CreateUserId] [int] NOT NULL,
18     [CreateDate] [datetime] NOT NULL,
19     [UpdateUserId] [int] NOT NULL,
20     [UpdateDate] [datetime] NOT NULL,
21     [IsDeleted] [bit] NOT NULL,
22  CONSTRAINT [PK_User] PRIMARY KEY CLUSTERED 
23 (
24     [Id] ASC
25 )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
26 ) ON [PRIMARY]
27 
28 GO
29 
30 ALTER TABLE [dbo].[User] ADD  CONSTRAINT [DF_User_UserName]  DEFAULT ('') FOR [UserName]
31 GO
32 
33 ALTER TABLE [dbo].[User] ADD  CONSTRAINT [DF_User_Password]  DEFAULT ('') FOR [Password]
34 GO
35 
36 ALTER TABLE [dbo].[User] ADD  CONSTRAINT [DF_User_Gender]  DEFAULT ((0)) FOR [Gender]
37 GO
38 
39 ALTER TABLE [dbo].[User] ADD  CONSTRAINT [DF_User_Birthday]  DEFAULT (getdate()) FOR [Birthday]
40 GO
41 
42 ALTER TABLE [dbo].[User] ADD  CONSTRAINT [DF_User_CreateUserId]  DEFAULT ((0)) FOR [CreateUserId]
43 GO
44 
45 ALTER TABLE [dbo].[User] ADD  CONSTRAINT [DF_User_CreateDate]  DEFAULT (getdate()) FOR [CreateDate]
46 GO
47 
48 ALTER TABLE [dbo].[User] ADD  CONSTRAINT [DF_User_UpdateUserId]  DEFAULT ((0)) FOR [UpdateUserId]
49 GO
50 
51 ALTER TABLE [dbo].[User] ADD  CONSTRAINT [DF_User_UpdateDate]  DEFAULT (getdate()) FOR [UpdateDate]
52 GO
53 
54 ALTER TABLE [dbo].[User] ADD  CONSTRAINT [DF_User_IsDeleted]  DEFAULT ((0)) FOR [IsDeleted]
55 GO
56 
57 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'主键Id' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'Id'
58 GO
59 
60 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'用户名' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'UserName'
61 GO
62 
63 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'密码' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'Password'
64 GO
65 
66 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'性别（0女，1男）' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'Gender'
67 GO
68 
69 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'出生年月日' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'Birthday'
70 GO
71 
72 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'创建人' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'CreateUserId'
73 GO
74 
75 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'创建时间' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'CreateDate'
76 GO
77 
78 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'更新人' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'UpdateUserId'
79 GO
80 
81 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'更新时间' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'UpdateDate'
82 GO
83 
84 EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'标志是否删除（0未删除，1已删除）' , @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE',@level1name=N'User', @level2type=N'COLUMN',@level2name=N'IsDeleted'
85 GO

 2、添加对应的User表实体

 1 /// <summary>
 2     /// 用户实体
 3     /// </summary>
 4     public class User : BaseModel
 5     {
 6         /// <summary>
 7         /// 用户名
 8         /// </summary>
 9         public string UserName { get; set; }
10 
11         /// <summary>
12         /// 密码
13         /// </summary>
14         public string Password { get; set; }
15 
16         /// <summary>
17         /// 性别（0女，1男）
18         /// </summary>
19         public bool Gender { get; set; }
20 
21         /// <summary>
22         /// 出生年月日
23         /// </summary>
24         public DateTime Birthday { get; set; }
25     }

3、使用泛型针对每一个表定义基本的CRUD接口，然后IUserRepository继承它，如果需要其他的接口，后续往里边定义即可

 1 /// <summary>
 2     /// 基类业务接口定义
 3     /// </summary>
 4     public interface IBaseBusiness<T> where T : class
 5     {
 6         /// <summary>
 7         /// 添加一个实体
 8         /// </summary>
 9         /// <param name="entity">要创建的实体</param>
10         /// <param name="connectionString">链接字符串</param>
11         /// <returns></returns>
12         bool CreateEntity(T entity, string connectionString = null);
13 
14         /// <summary>
15         /// 根据主键Id获取一个实体
16         /// </summary>
17         /// <param name="id">主键Id</param>
18         /// <param name="connectionString">链接字符串</param>
19         /// <returns></returns>
20         T RetriveOneEntityById(int id, string connectionString = null);
21 
22         /// <summary>
23         /// 获取所有实体
24         /// </summary>
25         /// <param name="connectionString">链接字符串</param>
26         /// <returns></returns>
27         IEnumerable<T> RetriveAllEntity(string connectionString = null);
28 
29         /// <summary>
30         /// 修改一个实体
31         /// </summary>
32         /// <param name="entity">要修改的实体</param>
33         /// <param name="connectionString">链接字符串</param>
34         /// <returns></returns>
35         bool UpdateEntity(T entity, string connectionString = null);
36 
37         /// <summary>
38         /// 根据主键Id删除一个实体
39         /// </summary>
40         /// <param name="id">主键Id</param>
41         /// <param name="connectionString">链接字符串</param>
42         /// <returns></returns>
43         bool DeleteEntityById(int id, string connectionString = null);
44     }

 4、主角进场。通过Nuget引入Dapper到Repository中，目前的版本为1.50.2

Install-Package Dapper

• Dapper是目前一款简洁、高效并且开源的ORM(实体对象关系映射)框架之一。
  传送门：https://github.com/StackExchange/Dapper
• 它不仅支持Sql Server，还适用于MySql，SqlLite，Oracle，PostgreSql等
• 默认使用参数化进行查询或者新增
• 支持存储过程
• 支持级联映射和多表映射
• 默认缓冲你所执行的SQL

a)、设置你的链接字符串和DbConnection

 1     /// <summary>
 2     /// 数据库配置
 3     /// </summary>
 4     public class DataBaseConfig
 5     {
 6         #region SqlServer链接配置
 7         /// <summary>
 8         /// 默认的Sql Server的链接字符串
 9         /// </summary>
10         private static string DefaultSqlConnectionString = @"Data Source=.;Initial Catalog=Light;User ID=sa;Password=sa;";
11         public static IDbConnection GetSqlConnection(string sqlConnectionString = null)
12         {
13             if (string.IsNullOrWhiteSpace(sqlConnectionString))
14             {
15                 sqlConnectionString = DefaultSqlConnectionString;
16             }
17             IDbConnection conn = new SqlConnection(sqlConnectionString);
18             conn.Open();
19             return conn;
20         }
21         #endregion
22     }

b)、实现IUserRepository定义的接口，使用Dapper进行操作数据

  1     /// <summary>
  2     /// 用户仓储
  3     /// </summary>
  4     /// <typeparam name="User"></typeparam>
  5     public class UserRepository : IUserRepository
  6     {
  7         /// <summary>
  8         /// 创建一个用户
  9         /// </summary>
 10         /// <param name="entity">用户</param>
 11         /// <param name="connectionString">链接字符串</param>
 12         /// <returns></returns>
 13         public bool CreateEntity(User entity, string connectionString = null)
 14         {
 15             using (IDbConnection conn = DataBaseConfig.GetSqlConnection(connectionString))
 16             {
 17                 string insertSql = @"INSERT INTO [dbo].[User]
 18                                            ([UserName]
 19                                            ,[Password]
 20                                            ,[Gender]
 21                                            ,[Birthday]
 22                                            ,[CreateUserId]
 23                                            ,[CreateDate]
 24                                            ,[UpdateUserId]
 25                                            ,[UpdateDate]
 26                                            ,[IsDeleted])
 27                                      VALUES
 28                                            (@UserName
 29                                            ,@Password
 30                                            ,@Gender
 31                                            ,@Birthday
 32                                            ,@CreateUserId
 33                                            ,@CreateDate
 34                                            ,@UpdateUserId
 35                                            ,@UpdateDate
 36                                            ,@IsDeleted)";
 37                 return conn.Execute(insertSql, entity) > 0;
 38             }
 39         }
 40 
 41         /// <summary>
 42         /// 根据主键Id删除一个用户
 43         /// </summary>
 44         /// <param name="id">主键Id</param>
 45         /// <param name="connectionString">链接字符串</param>
 46         /// <returns></returns>
 47         public bool DeleteEntityById(int id, string connectionString = null)
 48         {
 49             using (IDbConnection conn = DataBaseConfig.GetSqlConnection(connectionString))
 50             {
 51                 string deleteSql = @"DELETE FROM [dbo].[User]
 52                                             WHERE Id = @Id";
 53                 return conn.Execute(deleteSql, new { Id = id }) > 0;
 54             }
 55         }
 56 
 57         /// <summary>
 58         /// 获取所有用户
 59         /// </summary>
 60         /// <param name="connectionString">链接字符串</param>
 61         /// <returns></returns>
 62         public IEnumerable<User> RetriveAllEntity(string connectionString = null)
 63         {
 64             using (IDbConnection conn = DataBaseConfig.GetSqlConnection(connectionString))
 65             {
 66                 string querySql = @"SELECT [Id]
 67                                           ,[UserName]
 68                                           ,[Password]
 69                                           ,[Gender]
 70                                           ,[Birthday]
 71                                           ,[CreateUserId]
 72                                           ,[CreateDate]
 73                                           ,[UpdateUserId]
 74                                           ,[UpdateDate]
 75                                           ,[IsDeleted]
 76                                       FROM [dbo].[User]";
 77                 return conn.Query<User>(querySql);
 78             }
 79         }
 80 
 81         /// <summary>
 82         /// 根据主键Id获取一个用户
 83         /// </summary>
 84         /// <param name="id">主键Id</param>
 85         /// <param name="connectionString">链接字符串</param>
 86         /// <returns></returns>
 87         public User RetriveOneEntityById(int id, string connectionString = null)
 88         {
 89             using (IDbConnection conn = DataBaseConfig.GetSqlConnection(connectionString))
 90             {
 91                 string querySql = @"SELECT [Id]
 92                                           ,[UserName]
 93                                           ,[Password]
 94                                           ,[Gender]
 95                                           ,[Birthday]
 96                                           ,[CreateUserId]
 97                                           ,[CreateDate]
 98                                           ,[UpdateUserId]
 99                                           ,[UpdateDate]
100                                           ,[IsDeleted]
101                                       FROM [dbo].[User]
102                                      WHERE Id = @Id";
103                 return conn.QueryFirstOrDefault<User>(querySql, new { Id = id });
104             }
105         }
106 
107         /// <summary>
108         /// 修改一个用户
109         /// </summary>
110         /// <param name="entity">要修改的用户</param>
111         /// <param name="connectionString">链接字符串</param>
112         /// <returns></returns>
113         public bool UpdateEntity(User entity, string connectionString = null)
114         {
115             using (IDbConnection conn = DataBaseConfig.GetSqlConnection(connectionString))
116             {
117                 string updateSql = @"UPDATE [dbo].[User]
118                                        SET [UserName] = @UserName
119                                           ,[Password] = @Password
120                                           ,[Gender] = @Gender
121                                           ,[Birthday] = @Birthday
122                                           ,[UpdateUserId] = @UpdateUserId
123                                           ,[UpdateDate] = @UpdateDate
124                                           ,[IsDeleted] = @IsDeleted
125                                      WHERE Id = @Id";
126                 return conn.Execute(updateSql, entity) > 0;
127             }
128         }
129     }

上面的代码所执行的方法Execute，Query，QueryFirstOrDefault其实都是IDbConnection的扩展方法，转到定义你也可以清楚的看到默认buffered缓存是开启的，并且都支持事务提交，同时还都对应各自的async异步方法

public static IEnumerable<T> Query<T>(this IDbConnection cnn, string sql, object param = null, IDbTransaction transaction = null, bool buffered = true, int? commandTimeout = default(int?), CommandType? commandType = default(CommandType?));

 这样一来，再也不用DataReader去一个一个属性赋值了，也不用SqlParameter一个一个去参数化了，Dapper全部帮你做了，你只需要关注你的业务SQL语句以及上下文的对象即可，是不是很清爽！

c)、接下来就是完成对上一部分仓储数据的调用。一方面是IBusiness的服务接口定义，另一方面则是Business的简单实现，因为暂时只是涉及到一个表的增查改删，所以具体的代码就不上了

d)、至于依赖注入模块，我直接使用的是Microsoft.Extensions.DependencyInjection，所有的服务由ServiceCollection服务容器进行管理，我们只需要将接口和它的实现类进行注册就行了

 1     /// <summary>
 2     /// 注入业务逻辑层
 3     /// </summary>
 4     public class BusinessInjection
 5     {
 6         public static void ConfigureBusiness(IServiceCollection services)
 7         {
 8             services.AddSingleton<IUserBusiness, UserBusiness>();
 9         }
10     }

 1     /// <summary>
 2     /// 注入仓储层
 3     /// </summary>
 4     public class RepositoryInjection
 5     {
 6         public static void ConfigureRepository(IServiceCollection services)
 7         {
 8             services.AddSingleton<IUserRepository, UserRepository>();
 9         }
10     }

三、引入SwaggerUI

简介：SwaggerUI是一款针对WebApi的可视化工具，同样我也称它是一款全自动的接口描述文档，并且可以很方便的帮助你测试你的接口，接下来我们一步一步的来把它添加进去。

1、向ASP.NET Core WebApi项目中添加Swashbuckle组件，打开包管理控制台，输入：

Install-Package Swashbuckle -Pre

记得加上后边的-Pre，表示安装最新版本，否则的话会默认下载稳定版本5.5.3（不支持Core）

当然了，你也可以包管理器进行安装，记得勾选“包括预发行版”，然后选择6.0.0-beta902进行安装

2、打开Startup文件，添加Swagger中间件并将他们注入到应用程序的管道中，同时也将我们自定义的服务加进去

 1         /// <summary>
 2         /// This method gets called by the runtime. Use this method to add services to the container.
 3         /// </summary>
 4         /// <param name="services"></param>
 5         public void ConfigureServices(IServiceCollection services)
 6         {
 7             RepositoryInjection.ConfigureRepository(services);
 8             BusinessInjection.ConfigureBusiness(services);
 9             services.AddMvc();
10             services.AddSwaggerGen();
11         }
12 
13         /// <summary>
14         /// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
15         /// </summary>
16         /// <param name="app"></param>
17         /// <param name="env"></param>
18         /// <param name="loggerFactory"></param>
19         public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
20         {
21             loggerFactory.AddConsole(Configuration.GetSection("Logging"));
22             loggerFactory.AddDebug();
23 
24             app.UseMvc();
25             app.UseSwagger();
26             app.UseSwaggerUi();
27         }    

 3、打开launchSettings文件，修改launchUrl为“swagger/ui”

 1   "profiles": {
 2     "IIS Express": {
 3       "commandName": "IISExpress",
 4       "launchBrowser": true,
 5       "launchUrl": "swagger/ui",
 6       "environmentVariables": {
 7         "ASPNETCORE_ENVIRONMENT": "Development"
 8       }
 9     },
10     "Light.Api": {
11       "commandName": "Project",
12       "launchBrowser": true,
13       "launchUrl": "swagger/ui",
14       "environmentVariables": {
15         "ASPNETCORE_ENVIRONMENT": "Development"
16       },
17       "applicationUrl": "http://localhost:62116"
18     }
19   }

4、添加一个UserController，针对每一个服务增加一个REST风格的API接口。注意使用的HttpMethod方法。HttpGet表示获取对象，HttpPost表示创建对象，HttpPut表示修改对象，HttpDelete表示删除对象

 1     /// <summary>
 2     /// 用户控制器
 3     /// </summary>
 4     [Route("api/[controller]")]
 5     public class UserController : Controller
 6     {
 7         private readonly IUserBusiness iUserBusiness;
 8         /// <summary>
 9         /// 构造函数注入服务
10         /// </summary>
11         /// <param name="userBusiness"></param>
12         public UserController(IUserBusiness userBusiness)
13         {
14             iUserBusiness = userBusiness;
15         }
16 
17         /// <summary>
18         /// 获取所有用户
19         /// </summary>
20         /// <returns></returns>
21         [HttpGet]
22         //[Route("AllUser")]
23         public IEnumerable<User> GetAllUser()
24         {
25             return iUserBusiness.RetriveAllEntity();
26         }
27 
28         /// <summary>
29         /// 根据主键Id获取一个用户
30         /// </summary>
31         /// <param name="id">主键Id</param>
32         /// <returns></returns>
33         [HttpGet("{id}")]
34         public User GetOneUser(int id)
35         {
36             return iUserBusiness.RetriveOneEntityById(id);
37         }
38 
39         /// <summary>
40         /// 新增用户
41         /// </summary>
42         /// <param name="user">用户实体</param>
43         /// <returns></returns>
44         [HttpPost]
45         public bool CreateUser([FromBody]User user)
46         {
47             return iUserBusiness.CreateEntity(user);
48         }
49 
50         /// <summary>
51         /// 修改用户
52         /// </summary>
53         /// <param name="id">主键Id</param>
54         /// <param name="user">用户实体</param>
55         /// <returns></returns>
56         [HttpPut("{id}")]
57         public bool UpdateUser(int id, [FromBody]User user)
58         {
59             user.Id = id;
60             return iUserBusiness.UpdateEntity(user);
61         }
62 
63         /// <summary>
64         /// 根据主键Id删除一个用户
65         /// </summary>
66         /// <param name="id">主键Id</param>
67         /// <returns></returns>
68         [HttpDelete("{id}")]
69         public bool DeleteUser(int id)
70         {
71             return iUserBusiness.DeleteEntityById(id);
72         }
73     }

5、大功告成，Ctrl+F5运行你的程序，并试着执行添加，修改和查询的Api，体验Swagger带给你的方便之处。

写在最后：这篇文章只是介绍了它们俩最简单最基本的用法，如果其中说法有误的，还望各位前辈多多指点，更多的内容还需要后续的继续积累和学习，加油！