AutoMapper

Question

电影实体

    public class Movie
    {
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int Id { get; set; }
        public string Name { get; set; }
        public DateTime PublishDate { get; set; }
        public Genre Genre { get; set; }
        public int GenreId { get; set; }
        public Director Director { get; set; }
        public int DirectorId { get; set; }
        public List<Actor> Actors { get; set; }
        public decimal Price { get; set; }
    }

CreateMovieM dto

    public class CreateMovieM
    {
        public string Name { get; set; }
        public decimal Price { get; set; }
        public int DirectorId { get; set; }
        public int GenreId { get; set; }
        public string PublishDate { get; set; }
        public List<int> ActorsIds { get; set; }
    }

映射配置文件

CreateMap<int, Actor>()
    .ForMember(dest => dest.Id, opt => opt.MapFrom(src => src));

CreateMap<CreateMovieM, Movie>()
     .ForMember(dest => dest.Actors, opt => opt.MapFrom(src => src.ActorsIds));

创建命令

public class CreateMovieCommand
    {
        private readonly IMovieStoreDbContext _context;
        private readonly IMapper _mapper;
        private CreateMovieM _Model { get; set; }
        public CreateMovieCommand(IMovieStoreDbContext context, IMapper mapper, CreateMovieM model)
        {
            _context = context;
            _mapper = mapper;
            _Model = model;
        }

        public void Handle()
        {
            var movie = _context.Movies.SingleOrDefault(x => x.Name == _Model.Name);
            if (movie is not null)
                throw new InvalidOperationException("Movie already exists");

            movie = _mapper.Map<Movie>(_Model);

            _context.Movies.Add(movie);
            _context.SaveChanges();
        }
    }

这是数据生成器

public class DataGenerator
    {
        public static void Initialize(IServiceProvider services)
        {
            using var context = new MovieStoreDbContext(
            services.GetRequiredService<DbContextOptions<MovieStoreDbContext>>());

            var a1 = new Actor { Id = 1, Name = "Kemal", Surname = "Sunal" };
            var a2 = new Actor { Id = 2, Name = "Peri", Surname = "Baumeister" };
            var a3 = new Actor { Id = 3, Name = "Daniel", Surname = "Radcliffe" };

            var m1 = new Movie { Name = "Blood Red Sky", GenreId = 1, DirectorId = 2, Price = 10, PublishDate = new DateTime(1999, 5, 19), Actors = new List<Actor> { a2 } };
            var m2 = new Movie { Name = "Harry Potter", GenreId = 2, DirectorId = 3, Price = 15, PublishDate = new DateTime(1999, 5, 19), Actors = new List<Actor> { a3 } };
            var m3 = new Movie { Name = "Hababam Sinifi", GenreId = 3, DirectorId = 1, Price = 20, PublishDate = new DateTime(1999, 5, 19), Actors = new List<Actor> { a1 } };

            context.Movies.AddRange(
                new Movie { Id = 1, Name = "Blood Red Sky", GenreId = 1, DirectorId = 2, Price = 10, PublishDate = new DateTime(1999, 5, 19), Actors = new List<Actor> { a2 } },
                new Movie { Id = 2, Name = "Harry Potter", GenreId = 2, DirectorId = 3, Price = 15, PublishDate = new DateTime(1999, 5, 19), Actors = new List<Actor> { a3 } },
                new Movie { Id = 3, Name = "Hababam Sinifi", GenreId = 3, DirectorId = 1, Price = 20, PublishDate = new DateTime(1999, 5, 19), Actors = new List<Actor> { a1 }, }
                );

            context.Genres.AddRange(
                new Genre { Id = 1, Name = "Action" },
                new Genre { Id = 2, Name = "Science Fiction" },
                new Genre { Id = 3, Name = "Comedy" }
                );

            context.Directors.AddRange(
                new Director { Id = 1, Name = "Ertem", Surname = "Egilmez" },
                new Director { Id = 2, Name = "Peter", Surname = "Thorwarth" },
                new Director { Id = 3, Name = "Chris", Surname = "Columbus" }
               );

            context.SaveChanges();
        }
    }

示例输入

{   
    "name": "string",
    "price": 0,   
    "directorId": 1,   
    "genreId": 1,   
    "publishDate": "2020.1.1",   
    "actorsIds": [
       1   
     ]
}

我正在尝试将整数 ID 列表映射到演员列表，并在我输入演员 ID 之一的演员 ID 1 时出现“已添加具有相同键的项目。键：1”错误。

那么我应该如何配置自动映射器来执行此操作？

Answer 1

foreach (var actor in movie.Actors)
{
    _context.Entry(actor).State = EntityState.Unchanged;
}

感谢@GertArnold

，我通过在 SaveChanges() 方法之前添加该代码解决了我的问题

AutoMapper - 对象列表的整数列表

AutoMapper - list of ints to list of objects

c#

entity-framework-core

.net-core