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如何将AutoMapper添加到DI in。Net core 2.0控制台应用程序

automapper console-application .net-core c#

Uladz Kha · 技术社区 · 7 年前

我尝试使用 AutoMapper 在我的。Net Core 2.0控制台应用程序。我的班级是这样的:

public class AutoGetCurrency
{
    private readonly IMapper mapper;
    public AutoGetCurrency(IMapper mapper) {
    this.mapper = mapper;
    }
    ....
}

我试图将服务添加到 主要的 方法:

static void Main(string[] args)
{
    var services = new ServiceCollection();
    ServiceProvider = services.BuildServiceProvider();
    services.AddTransient<IMapper>();
    ....
}

但我有下一个错误 '发生了一个或多个错误。(对象引用未设置为对象的实例。)'

请告诉我如何添加AutoMapper以使用DI。

3 回复 | 直到 7 年前

Kahbazi 7 年前

您需要添加此nuget包 AutoMapper.Extensions.Microsoft.DependencyInjection 添加到项目并添加 AutoMapper 到您的 ServiceCollection 这样地

var services = new ServiceCollection();
services.AddAutoMapper(mapperConfig => mapperConfig.AddProfiles(GetType().Assembly))
ServiceProvider = services.BuildServiceProvider();

Iman Bahrampour 6 年前

安装“AutoMapper”和“Microsoft”。扩展。NuGet的DependencyInjection包。

实现User和UserDTO类,以便从User映射到UserDTO:

public class User
{
    public int Id { get; set; }
    public string Name { get; set; }
}
public class UserDTO
{
    public int Id { get; set; }
    public string Name { get; set; }
}

实现用于执行映射操作的接口和类,如下所示(不要忘记使用AutoMapper):

public interface ICustomMapper<T>
{
    T MapUserToUserDTO();
}
public class CustomMapper : ICustomMapper<UserDTO>
{
    private readonly IMapper mapper;
    public CustomMapper(IMapper mapper) =>
        this.mapper = mapper;
    public UserDTO MapUserToUserDTO()
    {
        User user = new User()
        {
           Id = 5,
           Name = "Iman"
        };
        UserDTO userDTO = mapper.Map<UserDTO>(user);
        return userDTO;
    }
}

之后,创建一个RegisterServices方法,用于在项目中进行依赖项注入,并创建一个DisposeServices方法,用于处理服务提供者。

using AutoMapper;
using Microsoft.Extensions.DependencyInjection;

namespace AutoMapperProject
{
    class Program
    {
        private static IServiceProvider _serviceProvider;
        static void Main(string[] args)
        {
            RegisterServices();
            ICustomMapper<UserDTO> service = 
            _serviceProvider.GetService<ICustomMapper<UserDTO>>();
            UserDTO userDTO = service.MapUserToUserDTO();
            DisposeServices();
            Console.WriteLine("Hello AutoMapper!");
        }
        private static void RegisterServices()
        {
            var collection = new ServiceCollection();
            collection.AddAutoMapper(typeof(Program));
            collection.AddScoped<ICustomMapper<UserDTO>, CustomMapper>();
            // ...
            // Add other services
            // ...
            _serviceProvider = collection.BuildServiceProvider();
        }
        private static void DisposeServices()
        {
           if (_serviceProvider == null)
           {
              return;
           }
           if (_serviceProvider is IDisposable)
           {
              ((IDisposable)_serviceProvider).Dispose();
           }
        }
    }
}

Anthony Giretti 7 年前

您需要映射一个实现IMapper的具体类。

http://automapper.readthedocs.io/en/latest/Dependency-injection.html

但情况是这样的: services.AddTransient<IMapper,YourconcreteClass>();