自动映射器合并对象问题

让自动映射器工作后（上一个问题 https://stackoverflow.com/questions/36602430/automapper-complex-types-mapping-exception），我正在解决另一个问题（把它带到另一个问题，所以第一个问题不会太复杂）......

我还有下一堂课：

public class Model1
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public DateTime BirthDay { get; set; }
    public int Gender { get; set; }
    public string NickName { get; set; }
}    
public class Model2
{
    public bool Married { get; set; }    
    public int Children { get; set; }
    public bool HasPet { get; set; }
}

public class Entity1
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public DateTime BirthDay { get; set; }
    public int Gender { get; set; }
}    
public class Entity2
{
    public bool Married { get; set; }    
    public int Children { get; set; }
    public bool HasPet { get; set; }
    public string NickName { get; set; }
}

除了名称和复杂性之外，这些对象与我的原始对象大致相似。

和 AutoMapper 配置类（从 Global.asax 调用）：

public class AutoMapperConfig
{
    public static MapperConfiguration MapperConfiguration { get; set; }

    public static void Configure()
    {
        MapperConfiguration = new MapperConfiguration(cfg => {
            cfg.AddProfile<Out>();
            cfg.CreateMap<SuperModel, SuperEntity>();
        });
        MapperConfiguration.AssertConfigurationIsValid();
    }
}

public class Out: Profile
{
   protected override void Configure()
    {
        CreateMap<Model1, Entity1>();
        CreateMap<Model2, Entity2>()
            .ForMember(dest => dest.NickName, opt => opt.Ignore());
        CreateMap<Model1, Entity2>()
            .ForMember(dest => dest.Married, opt => opt.Ignore())
            .ForMember(dest => dest.Children, opt => opt.Ignore())
            .ForMember(dest => dest.HasPet, opt => opt.Ignore());
        CreateMap<SuperModel, SuperEntity>()
            .ForMember(dest => dest.Entity1, opt => opt.MapFrom(src => src.Model1))
            .ForMember(dest => dest.Entity2, opt => opt.MapFrom(src => src.Model2));
    }
}

当我需要转换对象时，我下一步要做（此时我有_superModel初始化并填充数据）：

SuperEntity _superEntity = new SuperEntity();
AutoMapperConfig.MapperConfiguration.CreateMapper().Map<SuperModel, SuperEntity>(_superModel, _superEntity);

所以，我映射Model1 to Entity1（女巫很好），还有Model2 to Entity2（witch 也很好，除了 Id 属性，该属性被忽略）。

主要对象SuperModel and SuperEntity也被映射了，并且似乎工作得很好。

当我映射时出现问题Model1 to Entity2，得到NickName（认为​​其余属性被忽略）。总是如此null!

有任何想法吗？

问题是您想要映射目标属性（Entity2）来自多个源属性值（Children, Married and HasPet from Model2 and Nickname from Model1).

您可以使用以下方法解决您的情况自定义解析器 https://github.com/AutoMapper/AutoMapper/wiki/Custom-value-resolvers或与AfterMap https://github.com/AutoMapper/AutoMapper/wiki/Before-and-after-map-actions方法。

使用自定义解析器:

您必须创建一个继承自的类ValueResolver定义您将如何绘制地图Entity2从一个SuperModel:

public class CustomResolver : ValueResolver<SuperModel, Entity2>
{
    protected override Entity2 ResolveCore(SuperModel source)
    {
        return new Entity2
        {
            Children = source.Model2.Children,
            HasPet = source.Model2.HasPet,
            Married = source.Model2.Married,
            NickName = source.Model1.NickName
        };
    }
}

然后，像这样使用它：

CreateMap<SuperModel, SuperEntity>()
    .ForMember(dest => dest.Entity1, opt => opt.MapFrom(src => src.Model1))
    .ForMember(dest => dest.Entity2, opt => opt.ResolveUsing<CustomResolver>());

使用 AfterMap:

您可以在映射后执行操作，因此传递值Model1.Nickname to Entity2.Nickname地图之后：

CreateMap<SuperModel, SuperEntity>()
    .ForMember(dest => dest.Entity1, opt => opt.MapFrom(src => src.Model1))
    .ForMember(dest => dest.Entity2, opt => opt.MapFrom(src => src.Model2))
            .AfterMap((m, e) => e.Entity2.NickName = m.Model1.NickName);