.net Core 3 / API / DI / Repository pattern

Question

我正在尝试在.net Core中创建一个web API。我希望这个API调用一个实现了存储库设计模式的DLL。在整个过程中，我尝试使用依赖项注入，但我在管理存储库中数据库的上下文时遇到了一些问题。

我希望在API调用的每个生命周期中有一个新的上下文。

当我尝试执行代码时，在CreateHostBuilder(args(.Build((.Run((行出现异常；在Main中。

此例外情况为：

"无法构建某些服务"InvalidOperationException：在尝试激活"BX_Security_AccessBase.Repository.UsersReserve".时，无法解析类型为"BX_Scurity_AccessBase.Context.SecurityContext"的服务

我知道代码是不完整的，不会完全工作，但至少它应该比实际情况晚很多。我想我在架构上犯了一个错误。

下面有很多代码，但我无法隔离我的问题。

谢谢大家。

在我的API中，我有：

启动.cs

public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
public void ConfigureServices(IServiceCollection services)
{
services.AddControllers();
services.AddScoped<IUsersRepository, UsersRepository>();
services.AddScoped<IUserService, UserService>();
}
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseHttpsRedirection();
app.UseRouting();
app.UseAuthorization();
app.UseEndpoints(endpoints =>
{
endpoints.MapControllers();
});
}
}

用户.cs

public class User
{
public User() {}
public int UserId { get; set; }
public string LastName { get; set; }
public string FirstName { get; set; }
public DateTime Birthdate { get; set; }
}

UserService.cs

public class UserService : IUserService
{
private readonly AppSettings _appSettings;
private readonly IUsersRepository _userRepository;
public UserService(IOptions<AppSettings> appSettings, IUsersRepository userRepository)
{
_appSettings = appSettings.Value;
_userRepository = userRepository;
}
public IEnumerable<User> GetAll()
{
return _userRepository.GetAllUsers().Select(u=> new User());
}
}

IUserService.cs

public interface IUserService
{
public IEnumerable<User> GetAll();
}

AppSettings.cs

public class AppSettings
{
public string Secret { get; set; }
}

用户控制器.cs

[Route("api/[controller]")]
[ApiController]
public class UsersController : ControllerBase
{
private IUserService _userService { get; }
public UsersController(IUserService userService)
{
_userService = userService;
}
[HttpGet]
public IActionResult GetAll()
{
var users = _userService.GetAll();
return Ok(users);
}
}

在DLL中我有：

SecurityContext.cs

public partial class SecurityContext : DbContext
{
public SecurityContext(DbContextOptions<SecurityContext> options) : base(options) { }
public DbSet<Users> Users { get; set; }
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
if (!optionsBuilder.IsConfigured)
{
optionsBuilder.UseSqlServer("Data Source=; Database=BXDB; User Id=sa; Password=;");
}
}
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Users>(entity =>
{
entity.HasKey(e => e.UserId).HasName("PK_User_UserId");
entity.ToTable("Users", "sec");
entity.Property(e => e.Birthdate).HasColumnType("date");
entity.Property(e => e.FirstName)
.HasMaxLength(50)
.IsUnicode(false);
entity.Property(e => e.LastName)
.HasMaxLength(50)
.IsUnicode(false);
});
OnModelCreatingPartial(modelBuilder);
}
partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
}

用户的

public class Users
{
public Users() { }
public int UserId { get; set; }
public string LastName { get; set; }
public string FirstName { get; set; }
public DateTime Birthdate { get; set; }
}

IUsersPosition.cs

public interface IUsersRepository
{
public IQueryable<Users> GetAllUsers();
}

用户位置.cs

public class UsersRepository : IUsersRepository
{
public readonly SecurityContext _dbContext;
public UsersRepository(SecurityContext dbContext)
{
_dbContext = dbContext;
}
public IQueryable<Users> GetAllUsers()
{
return _dbContext.Users;
}
}

Answer 1

"无法构造某些服务"InvalidOperationException：在尝试激活"BX_Security_AccessBase.Context.SecurityContext"时，无法解析类型为"BX_Scurity_AccessBase.Repository.Userspository"的服务。

根据错误，您应该按照如下方式将DbContext注册为服务：

public void ConfigureServices(IServiceCollection services)
{ 
var connection = @"Server=(localdb)mssqllocaldb;Database=BXDB;Trusted_Connection=True;ConnectRetryCount=0";
services.AddDbContext<DLL.Models.SecurityContext>(options => options.UseSqlServer(connection, x => x.MigrationsAssembly("DLL")));
services.AddControllers();
services.AddScoped<IUsersRepository, UsersRepository>();
services.AddScoped<IUserService, UserService>();
}