手把手搭建基于.NET 8.0的Web API项目

1.背景

工作以后，大部分时间都是在做基于业务的CRUD工作，软件产品或者项目的框架基本都早就搭建好了，程序员只需要在框架内去填格子打代码就行了。于是，我抽了时间来搭建个简单的三层架构模式的web api项目，技术点大概如下：三层架构+EFCore+.Net 8.0 Web Api+AutoMap+IOC容器。本文是我搭建项目的一个过程，比较简单和粗糙，但是完整，适合学习和练手。

2.操作

2.1 项目的架构图

其实图1是我最开始的设计结构，但是设计风格有提到：模块间应该依赖抽象，而不是具体的实现。所以我将结构改造为了图2，针对业务逻辑层和数据访问层开了一个抽象接口层。

2.2 新增项目

按照如下操作，创建项目：SimpleWebApi

2.3 新增类库

按照下图新增类库：SimpleWebApi.Migration、SimpleWebApi.Business.Service、SimpleWebApi.Business.Service.Interface

注意：SimpleWebApi.Migration是数据库访问

SimpleWebApi.Business.Service、SimpleWebApi.Business.Service.Interface是做业务逻辑

2.4 支持EFCore

找到类库：SimpleWebApi.Migration，并给这个项目，添加如下nuget包：Microsoft.EntityFrameworkCore、Microsoft.EntityFrameworkCore.SqlServer、Microsoft.EntityFrameworkCore.Tools、Microsoft.EntityFrameworkCore.Design

按照如下所示：添加Model和DBContext

Commodity的代码如下：

using System;
using System.Collections.Generic;

namespace SimpleWebApi.Migration.Models;

public partial class Commodity
{
    public int Id { get; set; }

    public long? ProductId { get; set; }

    public int? CategoryId { get; set; }

    public string? Title { get; set; }

    public decimal? Price { get; set; }

    public string? Url { get; set; }

    public string? ImageUrl { get; set; }
}

CompanyInfo的代码如下：

using System;
using System.Collections.Generic;

namespace SimpleWebApi.Migration.Models;

public partial class CompanyInfo
{
    public int CompanyId { get; set; }

    public string? Name { get; set; }

    public DateTime? CreateTime { get; set; }

    public int CreatorId { get; set; }

    public int? LastModifierId { get; set; }

    public DateTime? LastModifyTime { get; set; }

    public virtual ICollection<SysUser> SysUsers { get; set; } = new List<SysUser>();
}

SysUser的代码如下：

using System;
using System.Collections.Generic;

namespace SimpleWebApi.Migration.Models;

public partial class SysUser
{
    public int Id { get; set; }

    public string? Name { get; set; }

    public string? Password { get; set; }

    public int Status { get; set; }

    public string? Phone { get; set; }

    public string? Mobile { get; set; }

    public string? Address { get; set; }

    public string? Email { get; set; }

    public long? Qq { get; set; }

    public string? WeChat { get; set; }

    public int? Sex { get; set; }

    public DateTime? LastLoginTime { get; set; }

    public DateTime? CreateTime { get; set; }

    public int? CreateId { get; set; }

    public DateTime? LastModifyTime { get; set; }

    public int? LastModifyId { get; set; }

    public int? CompanyId { get; set; }

    public virtual CompanyInfo? Company { get; set; }
}

AdvancedCustomerDbContext的代码如下：

using System;
using System.Collections.Generic;
using Microsoft.EntityFrameworkCore;
using SimpleWebApi.Migration.Models;

namespace SimpleWebApi.Migration
{

    public class AdvancedCustomerDbContext : DbContext
    {
        public AdvancedCustomerDbContext()
        {
        }

        public AdvancedCustomerDbContext(DbContextOptions<AdvancedCustomerDbContext> options)
            : base(options)
        {
        }

        public virtual DbSet<Commodity> Commodities { get; set; }

        public virtual DbSet<CompanyInfo> CompanyInfos { get; set; }

        public virtual DbSet<SysUser> SysUsers { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
#warning To protect potentially sensitive information in your connection string, you should move it out of source code. You can avoid scaffolding the connection string by using the Name= syntax to read it from configuration - see https://go.microsoft.com/fwlink/?linkid=2131148. For more guidance on storing connection strings, see https://go.microsoft.com/fwlink/?LinkId=723263.
            => optionsBuilder.UseSqlServer("Data Source=127.0.0.1;Initial Catalog=AdvancedCustomerDB_Init;Persist Security Info=True;User ID=sa;Password=****;Encrypt=False;TrustServerCertificate=true");

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Commodity>(entity =>
            {
                entity.ToTable("Commodity");

                entity.Property(e => e.ImageUrl)
                    .HasMaxLength(1000)
                    .IsUnicode(false);
                entity.Property(e => e.Price).HasColumnType("decimal(18, 2)");
                entity.Property(e => e.Title)
                    .HasMaxLength(500)
                    .IsUnicode(false);
                entity.Property(e => e.Url)
                    .HasMaxLength(1000)
                    .IsUnicode(false);
            });

            modelBuilder.Entity<CompanyInfo>(entity =>
            {
                entity.HasKey(e => e.CompanyId).HasName("PK_Company");

                entity.ToTable("CompanyInfo");

                entity.Property(e => e.CreateTime).HasColumnType("datetime");
                entity.Property(e => e.LastModifyTime).HasColumnType("datetime");
                entity.Property(e => e.Name)
                    .HasMaxLength(50)
                    .IsUnicode(false);
            });

            modelBuilder.Entity<SysUser>(entity =>
            {
                entity.ToTable("SysUser");

                entity.Property(e => e.Address)
                    .HasMaxLength(500)
                    .IsUnicode(false);
                entity.Property(e => e.CreateTime).HasColumnType("datetime");
                entity.Property(e => e.Email)
                    .HasMaxLength(50)
                    .IsUnicode(false);
                entity.Property(e => e.LastLoginTime).HasColumnType("datetime");
                entity.Property(e => e.LastModifyTime).HasColumnType("datetime");
                entity.Property(e => e.Mobile)
                    .HasMaxLength(12)
                    .IsUnicode(false);
                entity.Property(e => e.Name)
                    .HasMaxLength(50)
                    .IsUnicode(false);
                entity.Property(e => e.Password)
                    .HasMaxLength(50)
                    .IsUnicode(false);
                entity.Property(e => e.Phone)
                    .HasMaxLength(12)
                    .IsUnicode(false);
                entity.Property(e => e.Qq).HasColumnName("QQ");
                entity.Property(e => e.WeChat)
                    .HasMaxLength(50)
                    .IsUnicode(false);

                entity.HasOne(d => d.Company).WithMany(p => p.SysUsers)
                    .HasForeignKey(d => d.CompanyId)
                    .OnDelete(DeleteBehavior.Cascade)
                    .HasConstraintName("FK_SysUser_CompanyInfo");
            });

            OnModelCreatingPartial(modelBuilder);
        }

        public void OnModelCreatingPartial(ModelBuilder modelBuilder)
        {

        }
    }
}

2.5 业务逻辑抽象层

找到项目“SimpleWebApi.Business.Service.Interface”，新增项目引用-SimpleWebApi.Migration，如下图：

按照下图添加以下接口：

IBaseService的代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
using System.Threading.Tasks;

namespace SimpleWebApi.Business.Service.Interface
{
    public interface IBaseService
    {

        public IQueryable<T> Query<T>(Expression<Func<T,bool>> funcWhere) where T : class;
    }
}

ICommodityService的代码如下：

using SimpleWebApi.Migration.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SimpleWebApi.Business.Service.Interface
{
    public interface ICommodityService:IBaseService
    {

        public bool AddCommodity(Commodity commodity);

        public IQueryable<Commodity> GetCommodity(int Id);

     

    }
}

ICompanyInfoService的代码如下：

using SimpleWebApi.Migration.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SimpleWebApi.Business.Service.Interface
{
    public interface ICompanyInfoService:IBaseService
    {
        CompanyInfo GetCompany(int companyID);  
    }
}

ISysUserService的代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SimpleWebApi.Business.Service.Interface
{
    public interface ISysUserService:IBaseService
    {
    }
}

2.6 业务逻辑层

找到项目“SimpleWebApi.Business.Service”，新增项目引用如下：SimpleWebApi.Business.Service.Interface和 SimpleWebApi.Migration

按照下图添加以下类：

BaseService的代码如下：

using Microsoft.EntityFrameworkCore;
using SimpleWebApi.Business.Service.Interface;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
using System.Threading.Tasks;

namespace SimpleWebApi.Business.Service
{
    public class BaseService:IBaseService
    {
        protected DbContext Context;
        public BaseService(DbContext context)
        {
            Console.WriteLine($"{this.GetType().Name}被构造了......");
            this.Context= context;   
        }
        public IQueryable<T> Query<T>(Expression<Func<T, bool>> funcWhere) where T : class
        {
            return this.Context.Set<T>().Where<T>(funcWhere);   
        }
  
    }
}

CommodityService的代码如下：

using Microsoft.EntityFrameworkCore;
using SimpleWebApi.Business.Service.Interface;
using SimpleWebApi.Migration.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SimpleWebApi.Business.Service
{
    public class CommodityService : BaseService, ICommodityService
    {
        public CommodityService(DbContext context):base(context) 
        {
                
        }

        public bool AddCommodity(Commodity commodity)
        {
            this.Context.Set<Commodity>().Add(commodity);
            int num= this.Context.SaveChanges();
            return num > 0;
        }

        public IQueryable<Commodity> GetCommodity(int Id)
        {
            var list= this.Context.Set<Commodity>().Where(a => a.Id == Id);
            return list;
        }
    }
}

CompanyInfoService的代码如下：

using Microsoft.EntityFrameworkCore;
using SimpleWebApi.Business.Service.Interface;
using SimpleWebApi.Migration.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SimpleWebApi.Business.Service
{
    public class CompanyInfoService:BaseService, ICompanyInfoService
    {
        public CompanyInfoService(DbContext context):base(context)
        {
                
        }

        public CompanyInfo GetCompany(int companyID)
        {
            var company = this.Context.Set<CompanyInfo>().Where(a=>a.CompanyId==companyID).FirstOrDefault();
            return company; 
        }
    }
}

SysUserService的代码如下：

using Microsoft.EntityFrameworkCore;
using SimpleWebApi.Business.Service.Interface;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SimpleWebApi.Business.Service
{
    public class SysUserService:BaseService, ISysUserService
    {
        public SysUserService(DbContext context) : base(context)
        {
                
        }
    }
}

2.6 UI

找到项目“SimpleWebApi”，并新增项目引用：

SimpleWebApi.Business.Service、SimpleWebApi.Business.Service.Interface、SimpleWebApi.Migration

按照如下，新增nuget包引用：AutoMapper、AutoMapper.Extensions.Microsoft.DependencyInjection

新增文件夹DTO和Map,并新增类文件和AutoMapper的规则文件

CommodityDTO的代码如下：

using System;
using System.Collections.Generic;

namespace SimpleWebApi;

public class CommodityDTO
{
    public int CommodityId { get; set; }

    public long? ProductId { get; set; }

    public int? CategoryId { get; set; }

    public string? Title { get; set; }

    public decimal? Price { get; set; }

    public string? Url { get; set; }

    public string? ImageUrl { get; set; }
}

CompanyInfoDTO的代码如下：

using SimpleWebApi.Migration.Models;
using System;
using System.Collections.Generic;

namespace SimpleWebApi;

public class CompanyInfoDTO
{
    public int CompanyId { get; set; }

    public string? Name { get; set; }

    public DateTime? CreateTime { get; set; }

    public int CreatorId { get; set; }

    public int? LastModifierId { get; set; }

    public DateTime? LastModifyTime { get; set; }

    public virtual ICollection<SysUser> SysUsers { get; set; } = new List<SysUser>();
}

AuotoMapConfig的代码如下：

using AutoMapper;
using SimpleWebApi.Migration.Models;

namespace SimpleWebApi
{
    public class AuotoMapConfig:Profile
    {
        public AuotoMapConfig()
        {
            CreateMap<Commodity, CommodityDTO>().ForMember(c=>c.CommodityId, s=>s.MapFrom(c=>c.Id))
                .ForMember(c=>c.ProductId,s=>s.MapFrom(c=>c.ProductId))
                .ForMember(c=>c.CategoryId,s=>s.MapFrom(c=>c.CategoryId))
                .ForMember(c=>c.Title,s=>s.MapFrom(c=>c.Title))
                .ForMember(c=>c.Price,s=>s.MapFrom(c=>c.Price))
                .ForMember(c=>c.Url,s=>s.MapFrom(c=>c.Url))
                .ForMember(c=>c.ImageUrl,s=>s.MapFrom(c=>c.ImageUrl));

            CreateMap<CompanyInfo, CompanyInfoDTO>();

        }

    }
}

为了添加对象映射，DBContext，对象注入等，打开Program文件，按照如下添加

上图的红色代码如下：

  //查询数据库真实数据的业务逻辑层服务注册
  builder.Services.AddTransient<ICommodityService, CommodityService>();
  builder.Services.AddTransient<ICompanyInfoService, CompanyInfoService>();

  //添加DbContext
  //builder.Services.AddDbContext<AdvancedCustomerDbContext>();
  builder.Services.AddTransient<DbContext, AdvancedCustomerDbContext>();

  //支持AutoMapper
  builder.Services.AddAutoMapper(options =>
  {
      options.AddProfile<AuotoMapConfig>();

  });

选中“Controllers”文件夹新增控制器 ApiController

ApiController代码如下：

using AutoMapper;
using Microsoft.AspNetCore.Mvc;
using SimpleWebApi.Business.Service.Interface;
using SimpleWebApi.Migration.Models;
using System.Linq.Expressions;

namespace SimpleWebApi.Controllers
{
    [ApiController]
    [Route("api/[controller]/[action]")]
    public class ApiController : ControllerBase
    {
        private readonly ILogger<ApiController> _logger;

        private ICommodityService _comService;
        private ICompanyInfoService _companyService;

        private IMapper _mapper;

        public ApiController(ILogger<ApiController> logger, ICommodityService comService, ICompanyInfoService companyService, IMapper mapper)
        {
            _logger = logger;
            _comService = comService;
            _companyService = companyService;
            _mapper = mapper;
        }

        [HttpGet]
        public IEnumerable<CommodityDTO> GetCommodity(int Id)
        {
            Expression<Func<Commodity, bool>> funcWhere = null;
            funcWhere = a => a.Id == Id;
            var commodityList = _comService.Query(funcWhere);
            List<CommodityDTO> list = new List<CommodityDTO>();
            _mapper.Map<IQueryable<Commodity>, List<CommodityDTO>>(commodityList, list);

            return list;

        }

        [HttpGet]
        public CompanyInfoDTO GetCompanyInfo(int companyId)
        {
            var company = _companyService.GetCompany(companyId);
            CompanyInfoDTO dto = new CompanyInfoDTO();
            _mapper.Map<CompanyInfo, CompanyInfoDTO>(company, dto);

            return dto;

        }
    }
}

这里有个小坑，打开SimpleWebApi.csproj，按照下图设置，可以解决问题

<InvariantGlobalization>false</InvariantGlobalization>

ps：默认该数据值是true，运行程序后会异常，异常提示如下:

System.Globalization.CultureNotFoundException
  HResult=0x80070057
  Message=Only the invariant culture is supported in globalization-invariant mode. See https://aka.ms/GlobalizationInvariantMode for more information. (Parameter 'name')
en-us is an invalid culture identifier.
  Source=System.Private.CoreLib
  StackTrace:
   在 System.Globalization.CultureInfo.GetCultureInfo(String name)
   在 Microsoft.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry, SqlConnectionOverrides overrides)
   在 Microsoft.Data.SqlClient.SqlConnection.Open(SqlConnectionOverrides overrides)
   在 Microsoft.Data.SqlClient.SqlConnection.Open()
   在 Microsoft.EntityFrameworkCore.SqlServer.Storage.Internal.SqlServerConnection.OpenDbConnection(Boolean errorsExpected)
   在 Microsoft.EntityFrameworkCore.Storage.RelationalConnection.OpenInternal(Boolean errorsExpected)
   在 Microsoft.EntityFrameworkCore.Storage.RelationalConnection.Open(Boolean errorsExpected)
   在 Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteReader(RelationalCommandParameterObject parameterObject)
   在 Microsoft.EntityFrameworkCore.Query.Internal.SingleQueryingEnumerable`1.Enumerator.InitializeReader(Enumerator enumerator)
   在 Microsoft.EntityFrameworkCore.Query.Internal.SingleQueryingEnumerable`1.Enumerator.<>c.<MoveNext>b__21_0(DbContext _, Enumerator enumerator)
   在 Microsoft.EntityFrameworkCore.SqlServer.Storage.Internal.SqlServerExecutionStrategy.Execute[TState,TResult](TState state, Func`3 operation, Func`3 verifySucceeded)
   在 Microsoft.EntityFrameworkCore.Query.Internal.SingleQueryingEnumerable`1.Enumerator.MoveNext()
   在 System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   在 System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
   在 SimpleProjectDemo.Controllers.WeatherForecastController.Get2() 在 E:Vs_ProjectSimpleProjectDemoSimpleProjectDemoControllersWeatherForecastController.cs 中: 第 50 行
   在 Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.SyncObjectResultExecutor.Execute(ActionContext actionContext, IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
   在 Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<<InvokeActionMethodAsync>g__Logged|12_1>d.MoveNext()

2.7 运行项目

运行项目，如下图所示显示Swagger页面:

用接口api/Api/GetCommodity 来测试下

3.结论

至此，操作完成。成功的搭建了一个简单的.net 8.0的web api项目。