Asp.net core 如何将服务从.net core di容器传递到使用automapper创建的新对象

我面临一个场景，需要将asp.net核心DI容器中的服务注入到使用automapper创建的对象的构造函数中

我不知道这是否是最佳实践，但让我解释一下我正在努力实现的目标

我有一个asp.net核心mvc控制器，它接收一个模型参数，只是一个POCO，该模型需要转换为一个ViewModel类，其中包含一些业务逻辑、数据访问等，在该类对象中，我想从注入的服务中获取一些信息，这是我遇到问题的部分，无法确定如何将服务从控制器注入到最终的ViewModel

我现在的代码看起来像这样

NewGameModel.cs

namespace MyProject.Shared.Models
{
    public class NewGameModel
    {
        public List<PlayerModel> Players { get; set; }

        public bool IsValid => Players.Any();

        public NewGameModel()
        {
            Players = new List<PlayerModel>();
        }
    }
}

namespace MyProject.Core.ViewModels
{
    public class NewGameViewModel
    {
        private Guid Token = Guid.NewGuid();
        private DateTime DateTimeStarted = DateTime.Now;
        private readonly IConfiguration _configuration;

        public List<PlayerModel> Players { get; set; }

        public NewGameViewModel(IConfiguration config)
        {
            _configuration = config;
        }

        public string DoSomething()
        {
            //Do something using _configuration

            //Business Logic, Data Access etc
        }
    }
}

namespace MyProject.Service
{
    public class MapperProfile : Profile
    {
        public MapperProfile()
        {
            CreateMap<NewGameModel, NewGameViewModel>();
        }
    }
}

namespace MyProject.Service
{
    public class Startup
    {
        public IConfiguration Configuration { get; }

        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();
            services.AddSingleton(Configuration);

            var autoMapperConfig = new MapperConfiguration(cfg =>
            {
                cfg.AddProfile(new MapperProfile());
            });

            var mapper = autoMapperConfig.CreateMapper();

            services.AddSingleton(mapper);
        }

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseMvc();
        }
    }
}

namespace MyProject.Service.Controllers
{
    [Route("api/[controller]")]
    public class GameController : Controller
    {
        private readonly IConfiguration _configuration;
        private readonly IMapper _mapper;

        public GameController(IConfiguration config, IMapper mapper)
        {
            _configuration = config;
            _mapper = mapper;
        }

        [HttpPost]
        public IActionResult CreateNewGame([FromBody]NewGameModel model)
        {
            if (!model.IsValid) return BadRequest();

            //Throws error because no constructor parameter was passed    
            //How to pass the IConfiguration to the destination NewGameViewModel object?

            var viewModel = _mapper.Map<NewGameModel, NewGameViewModel>(model);

            var result = viewModel.DoSomething();

            return CreatedAtRoute("GetGame", new { token = result.GameToken }, result);
        }
    }
}

ASP.NET核心项目-GameController.cs

namespace MyProject.Shared.Models
{
    public class NewGameModel
    {
        public List<PlayerModel> Players { get; set; }

        public bool IsValid => Players.Any();

        public NewGameModel()
        {
            Players = new List<PlayerModel>();
        }
    }
}

namespace MyProject.Core.ViewModels
{
    public class NewGameViewModel
    {
        private Guid Token = Guid.NewGuid();
        private DateTime DateTimeStarted = DateTime.Now;
        private readonly IConfiguration _configuration;

        public List<PlayerModel> Players { get; set; }

        public NewGameViewModel(IConfiguration config)
        {
            _configuration = config;
        }

        public string DoSomething()
        {
            //Do something using _configuration

            //Business Logic, Data Access etc
        }
    }
}

namespace MyProject.Service
{
    public class MapperProfile : Profile
    {
        public MapperProfile()
        {
            CreateMap<NewGameModel, NewGameViewModel>();
        }
    }
}

namespace MyProject.Service
{
    public class Startup
    {
        public IConfiguration Configuration { get; }

        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();
            services.AddSingleton(Configuration);

            var autoMapperConfig = new MapperConfiguration(cfg =>
            {
                cfg.AddProfile(new MapperProfile());
            });

            var mapper = autoMapperConfig.CreateMapper();

            services.AddSingleton(mapper);
        }

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseMvc();
        }
    }
}

namespace MyProject.Service.Controllers
{
    [Route("api/[controller]")]
    public class GameController : Controller
    {
        private readonly IConfiguration _configuration;
        private readonly IMapper _mapper;

        public GameController(IConfiguration config, IMapper mapper)
        {
            _configuration = config;
            _mapper = mapper;
        }

        [HttpPost]
        public IActionResult CreateNewGame([FromBody]NewGameModel model)
        {
            if (!model.IsValid) return BadRequest();

            //Throws error because no constructor parameter was passed    
            //How to pass the IConfiguration to the destination NewGameViewModel object?

            var viewModel = _mapper.Map<NewGameModel, NewGameViewModel>(model);

            var result = viewModel.DoSomething();

            return CreatedAtRoute("GetGame", new { token = result.GameToken }, result);
        }
    }
}

名称空间MyProject.Service.Controllers
{
[路由（“api/[控制器]”）]
公共类游戏控制器：控制器
{
专用只读IConfiguration\u配置；
专用只读IMapper\u映射器；
公共游戏控制器（IConfiguration配置，IMapper映射器）
{
_配置=配置；
_映射器=映射器；
}
[HttpPost]
public IActionResult CreateNewGame（[FromBody]NewGameModel模型）
{
如果（！model.IsValid）返回BadRequest（）；
//引发错误，因为未传递任何构造函数参数
//如何将IConfiguration传递到目标NewGameViewModel对象？
var viewModel=\u mapper.Map（model）；
var result=viewModel.DoSomething（）；
返回CreatedAtRoute（“GetGame”，new{token=result.GameToken}，result）；
}
}
}

---

非常感谢您的帮助

更新配置文件，将配置作为注入依赖项，并在创建映射时使用

ConstructUsing

公共类MapperProfile:Profile{
公共映射配置文件（IConfiguration配置）{
CreateMap（）
.ConstructUsing（=>NewGameViewModel（config））；
}
}

对于后面的方法，不推荐使用上面的方法，因为它在配置文件中有状态。相反，请使用

AutoMapper.Extensions.Microsoft.DependencyInjection

软件包并在您的启动中：

services.AddAutoMapper();

然后在您的配置文件中，只需告诉AutoMapper您希望使用容器构造目标对象：

public class MapperProfile : Profile
{
    public MapperProfile()
    {
        CreateMap<NewGameModel, NewGameViewModel>()
            .ConstructUsingServiceLocator();
    }
}

公共类MapperProfile:Profile
{
公共MapperProfile（）
{
CreateMap（）
.ConstructionUsingServiceLocator（）；
}
}

---

然后，您的控制器可以依赖于

IMapper

，AutoMapper将使用DI容器构建视图模型，您对ASP.NET核心的配置将只是

services.AddAutoMapper（）的一行
查看此项。仍然在试图弄清楚如何将配置放入配置文件中，但还有一个问题是，按照您的建议更改MapperProfile，并将服务传递给Startup中的构造函数参数。cs成功了，谢谢