在 .NET CORE 2.2 Web API 应用程序中配置 AutoMapper

Question

我在我的 Web API 应用程序中配置了 AutoMapper 'AutoMapper.Extensions.Microsoft.DependencyInjection 版本 7.0'，如下所示；我收到 Missing Type Map 配置映射错误。

启动

  public void ConfigureServices(IServiceCollection services)
    {
        services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);

        services.AddDbContext<SupplierContext>(options =>
                options.UseInMemoryDatabase(databaseName: "MyDatabase"));

        services.AddTransient<IAppService, AppService>();

        var profiles = from type in typeof(Startup).Assembly.GetTypes()
                       where typeof(Profile).IsAssignableFrom(type)
                       select (Profile)Activator.CreateInstance(type);

        var mapConfig = new MapperConfiguration(cfg =>
        {
            foreach (var profile in profiles)
            {
                cfg.AddProfile(profile);
            }
        });

        var mapper = mapConfig.CreateMapper();

        services.AddSingleton(mapper);
    }

我在文件夹下的主项目 API 中创建了一个配置文件

简介

 public UserProfile()
    {
        CreateMap<User, UserDataView>()
            .ForMember(dest => dest.Id, opt => opt.MapFrom(dataModel => dataModel.Id))
            .ForMember(dest => dest.Title, opt => opt.MapFrom(dataModel => dataModel.Title))
            .ForMember(dest => dest.FirstName, opt => opt.MapFrom(dataModel => dataModel.FirstName))
            .ForMember(dest => dest.LastName, opt => opt.MapFrom(dataModel => dataModel.LastName))
            .ForMember(dest => dest.ActivationDate, opt => opt.MapFrom(dataModel => dataModel.ActivationDate));

        //CreateMap<User, UserDataView>()
        //    .ReverseMap();

    }

用户类

public class User
{
  
    public Guid Id { get; set; }

    public string Title { get; set; }

    public string FirstName { get; set; }

    public string LastName { get; set; }

    public DateTime ActivationDate { get; set; }

}

当我尝试将模型数据映射到 Dto 时，出现缺少类型映射配置错误

错误

Missing type map configuration or unsupported mapping.

 Mapping types:
 Task`1 -> List`1
 System.Threading.Tasks.Task`1[[System.Collections.Generic.List`1[[MyApp.Model.User.User, MyApp.Model, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]], System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea70000]] -> System.Collections.Generic.List`1[[MyApp.Model.DTOs.UserDataView, MyApp.Model, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]

自动映射

 var UserDataModel = (from user in _context.Users
                   join email in _context.Emails on user.Id equals email.userId into se
                   join phone in _context.Phones on user.Id equals phone.userId into sp
                   select new User 
                   {
                       Id = user.Id,
                       Title = user.Title,
                       FirstName = user.FirstName,
                       LastName = user.LastName,
                       ActivationDate = user.ActivationDate,
                   }).ToListAsync();

var dataResult = _mapper.Map<List<UserDataView>>(UserDataModel);

Answer 1

我发现了我的错误。 UserDataModel 属于 Task 类型，而我的配置文件类预期会有所不同。

我已将我的 LINQ 脚本更改如下，它确实有效

var UserDataModel = (from user in _context.Users
               join email in _context.Emails on user.Id equals email.userId into se
               join phone in _context.Phones on user.Id equals phone.userId into sp
               select new User 
               {
                   Id = user.Id,
                   Title = user.Title,
                   FirstName = user.FirstName,
                   LastName = user.LastName,
                   ActivationDate = user.ActivationDate,
               });

 var ddf = _mapper.Map<List<SupplierDataView>>(supplierDataModel);