最近在学习.Net Core，于是也了解到了AutoMapper。

首先要 nuget添加下AutoMapper 我这次装的版本号是6.10的。

第一种方法 是想在Controller中使用的

1.新建个配置类 以便之后初始化AutoMapper

    public partial class AutoMapperConfiguration : Profile
    {
        public AutoMapperConfiguration()
        {
            CreateMap<UserEntity, UserDto>().ForMember(u => u.Status, e => e.MapFrom(s => (UserStatus)s.Status));
            CreateMap<UserDto, UserEntity>().ForMember(u => u.Status, e => e.MapFrom(s => (byte)s.Status));
        }
    }

2.在Startup.cs中加一个属性

private MapperConfiguration _mapperConfiguration { get; set; }

3.在Start方法中增加

            _mapperConfiguration = new MapperConfiguration(cfg =>
            {
                cfg.AddProfile(new AutoMapperConfiguration());
            });

4.在ConfigureServices方法中增加

  services.AddSingleton(sp => _mapperConfiguration.CreateMapper());

5.就可以在Controller中使用了

        private readonly IMapper _mapper;
        public HomeController(IMapper mapper)
        {
            _mapper = mapper;
        }
       public IActionResult Index()
        {
            UserEntity user = new UserEntity { LoginName = "admin", RealName = "管理员" };
            var model = _mapper.Map<UserEntity, UserDto>(user);   //实现UserEntity对于UserDto的转换
            return View();
        }

第二种方法 在Service中使用

  public class ServiceBase
    {
        public readonly IMapper _mapper;
        public ServiceBase()
        {
            var mapperConfiguration = new MapperConfiguration(cfg =>
            {
                cfg.AddProfile(new AutoMapperConfiguration());
            });
            _mapper = mapperConfiguration.CreateMapper();
        }
        public void TestMapper()
        {
             List list = new List
            {
              new UserEntity { LoginName = "admin", RealName = "管理员" },
              new UserEntity { LoginName = "admin", RealName = "管理员" },
            };
            var resullt = _mapper.Map<List<UserEntity>, List<UserDto>>(list); //实现集合转集合
       }
   }