Question

我正在尝试在Entity Framework Core中映射实体，并遇到以下错误。我有两个主要实体Person和PersonNote，它们之间具有一对多的关系。

一个人可以有很多人的笔记。我尝试检索伪造品的方法不会返回结果，但是在尝试映射时失败。正如您在我的帖子中看到的那样，我定义了两个映射。一种是将PersonNote与Person映射，以便可以评估AuthorName。中的AuthorId 与个人ID相关的PersonNote。

我的PersonNote模型包含AuthorName，但DataModel不包含。我正在尝试在createmap函数中映射该值。我错过了什么吗？

缺少类型映射配置或不支持的映射。\ r \ n \ r \ n映射类型：\ r \ nEntityQueryable`1->

我定义了以下模型

    namespace Genistar.Organisation.Models.User
    {
        public class PersonNote
        {
            public PersonNote()
            {
                 Person = new HashSet<Person>();
            }

            public int Id { get; set; }
            public int PersonId { get; set; }
            public string Note { get; set; }
            public int AuthorId { get; set; }
            public string AuthorName { get; set; }
            public string CreatedBy { get; set; }
            public DateTime Created { get; set; }

            public ICollection<Person> Person { get; set; }
        }
    }

namespace Genistar.Organisation.Models.DataModels
{
        [Table(nameof(PersonNote), Schema = "common")]
        public class PersonNote
        {
            public int Id { get; set; }
            public int PersonId { get; set; }
            public string Note { get; set; }
            public int AuthorId { get; set; }
            public string CreatedBy { get; set; }
            public DateTime Created { get; set; }
            [DatabaseGenerated(DatabaseGeneratedOption.Computed)]
            public DateTime RecordStartDateTime { get; set; }
            [DatabaseGenerated(DatabaseGeneratedOption.Computed)]
            public DateTime RecordEndDateTime { get; set; }
        }
    }

    namespace Genistar.Organisation.Models.DataModels
    {
        public class Person
        {
            public int Id { get; set; }
            public int? TitleId { get; set; }
            public string FirstName { get; set; }
            public string FirstNamePref { get; set; }
            public string MiddleName { get; set; }
            public string LastName { get; set; }
            public DateTime? DateOfBirth { get; set; }
            public string Gender { get; set; }
            public int AddressId { get; set; }
            public string TelephoneNumber { get; set; }
            public string MobileNumber { get; set; }
            public string Email { get; set; }
            public int? PartnerId { get; set; }
            public bool Enabled { get; set; }
            public string CreatedBy { get; set; }
            public DateTime Created { get; set; }
            public string ModifiedBy { get; set; }
            public DateTime Modified { get; set; }
            [DatabaseGenerated(DatabaseGeneratedOption.Computed)]
            public DateTime RecordStartDateTime { get; set; }
            [DatabaseGenerated(DatabaseGeneratedOption.Computed)]
            public DateTime RecordEndDateTime { get; set; }
            public Address Address { get; set; }
            public Title Title { get; set; }
            public Client Client { get; set; }

            public List<PersonNote> PersonNotes { get; set; }
        }
    }

CreateMap函数

 CreateMap<Genistar.Organisation.Models.DataModels.Person, Genistar.Organisation.Models.User.PersonNote>()
                .ForMember(t => t.AuthorId, opt => opt.MapFrom(s => s.Id))
                .ForMember(t => t.AuthorName, opt => opt.MapFrom(s => s.FirstName + " " + s.LastName));

CreateMap<Genistar.Organisation.Models.DataModels.PersonNote, Genistar.Organisation.Models.User.PersonNote>()
                  //.ForMember(t => t.Id, opt => opt.MapFrom(s => s.Id))
                  //.ForMember(t => t.PersonId, opt => opt.MapFrom(s => s.PersonId))
                  //.ForMember(t => t.Note, opt => opt.MapFrom(s => s.Note))
                  //.ForMember(t => t.AuthorId, opt => opt.MapFrom(s => s.AuthorId))
                  //.ForMember(t => t.CreatedBy, opt => opt.MapFrom(s => s.CreatedBy))
                  //.ForMember(t => t.Created, opt => opt.MapFrom(s => s.Created));

                .ForMember(t => t.Id, opt => opt.Ignore())
               .ForMember(t => t.PersonId, opt => opt.Ignore())
               .ForMember(t => t.Note, opt => opt.Ignore())
               .ForMember(t => t.AuthorId, opt => opt.Ignore())
               .ForMember(t => t.CreatedBy, opt => opt.Ignore())
               .ForMember(t => t.Created, opt => opt.Ignore());

查询-请注意，此处返回的PersonNote类型为Genistar.Organisation.Models.User.PersonNote

[FunctionName(nameof(GetPersonNote))]
[UsedImplicitly]
public Task<IActionResult> Run([HttpTrigger(AuthorizationLevel.Anonymous, "get", Route = "person-note/{id}")] HttpRequest req,
            int id) => _helper.HandleAsync(async () =>
                               {
                                   var personNotes = _organisationRepository.GetPersonNotes(id);
                                   return new OkObjectResult(_mapper.Map<PersonNote>(personNotes));
                               });

 public IEnumerable<PersonNote> GetPersonNotes(int personId)
 {
     var PersonNotes1 = _context.PersonNotes.Where(p => p.PersonId == personId);
     return PersonNotes1;
 }

Answer 1

这里的示例没有意义，在同一名称空间中不能有2个“ PersonNote”类。看起来您拥有Entities，然后分离了ViewModels / DTO，尽管这样会使相同的命名混淆。如果需要或要求，那么我建议为命名空间起别名。即：

using Models = Genistar.Organisation.Models;
using DTOs = Genistar.Organisation.Models.DataModels;

以便使代码清楚地知道哪个是什么。

例如，此代码没有多大意义：

public Task<IActionResult> Run([HttpTrigger(AuthorizationLevel.Anonymous, "get", Route = "person-note/{id}")] HttpRequest req,
        int id) => _helper.HandleAsync(async () =>
{
    var personNotes = _organisationRepository.GetPersonNotes(id);
    return new OkObjectResult(_mapper.Map<PersonNote>(personNotes));
});

public IEnumerable<PersonNote> GetPersonNotes(int personId)
{
    var PersonNotes1 = _context.PersonNotes.Where(p => p.PersonId == personId);
    return PersonNotes1;
}

我假设它们是从2个不同的类中提取的，因为第一种方法看起来应该处理DTO，而第二种方法应该是从存储库处理实体？

有些事情确实很突出。首先，存储库方法应返回IQueryable<T>而不是IEnumerable<T>。这样做的好处是，它将允许您进一步链接Linq表达式，包括允许Automapper将设置减少到DTO，并将该优化传递到组合的SQL。

第二件事是利用Automapper的ProjectTo方法而不是Map。与IQueryable结合使用，可以在SQL级别完成映射：

因此存储库方法更改为：

public IQueryable<PersonNote> GetPersonNotes(int personId)
{
    var PersonNotes1 = _context.PersonNotes.Where(p => p.PersonId == personId);
    return PersonNotes1;
}

然后输入您的控制器代码：

public Task<IActionResult> Run([HttpTrigger(AuthorizationLevel.Anonymous, "get", Route = "person-note/{id}")] HttpRequest req,
        int id) => _helper.HandleAsync(async () =>
    {
       var personNotes = _organisationRepository.GetPersonNotes(id).ProjectTo<DTO.PersonNote>(_mapper.ConfigurationProvider);
       return new OkObjectResult(personNotes);
    });

当您的存储库返回IEnumerable时，映射器调用将根据急切加载的内容尝试浏览面值的属性，并处理EF插入的任何代理类型。对于不同的EF Core版本与EF6之间的区别，我不是100％的，但是您现有的代码似乎会因代理类型而被绊倒。即便如此，否则，Automapper的Map调用会在遍历属性时延迟加载任何相关实体，从而会给数据库带来额外的打击。

实体框架核心3-缺少类型映射配置或不支持的映射

1 个答案: