Automapper：如何不从复杂类型重复映射配置基类

Question

我有一大堆的DTO类，从这个CardBase继承：

// base class 
public class CardBase 
{ 
    public int TransId {get; set; } 
    public string UserId { get; set; } 
    public int Shift { get; set; } 
} 

// one of the concrete classes 
public class SetNewCardSettings : CardBase 
{ 
    // specific properties ... 
} 

在我的MVC项目我有一个一帮视图模型AuditVm复杂类型，有CardBase相同的属性：

public class AuditVm 
{ 
    public int TransId {get; set; } 
    public string UserId { get; set; } 
    public int Shift { get; set; } 
} 

public class CreateCardVm : CardVm 
{ 
    // specific properties here ... 

    public AuditVm Audit { get; set } 
} 

这些视图模型不能从AuditVm继承，因为他们每个人已经有母。我认为我可以像下图一样设置我的映射，因此我不必为AuditVm为复杂类型的每个视图模型指定从AuditVm到CardBase的映射。但它不起作用。我如何正确地从复杂类型映射到具有基类属性的扁平类型？

Mapper.CreateMap<AuditorVm, CardBase>() 
    .Include<AuditorVm, SetNewCardSettings>(); 

    // this does not work because it ignores my properties that I map in the second mapping 
    // if I delete the ignore it says my config is not valid 
    Mapper.CreateMap<AuditorVm, SetNewCardSettings>() 
    .ForMember(dest => dest.Temp, opt => opt.Ignore()) 
    .ForMember(dest => dest.Time, opt => opt.Ignore()); 

    Mapper.CreateMap<CreateCardVm, SetNewCardSettings>() 
    // this gives me an error 
    .ForMember(dest => dest, opt => opt.MapFrom(src => Mapper.Map<AuditorVm, SetNewCardSettings>(src.Auditor))); 

    // I also tried this and it works, but it does not map my specific properties on SetNewCardSettings 
    //.ConvertUsing(dest => Mapper.Map<AuditorVm, SetNewCardSettings>(dest.Auditor)); 

UPDATE： 这里是小提琴https://dotnetfiddle.net/iccpE0

Answer 1

.Include是一个非常特殊的情况下 - 你有两个相同结构的类层次结构要映射，例如：

public class AEntity : Entity { } 

public class BEntity : Entity { } 

public class AViewModel : ViewModel { } 

public class BViewModel : ViewModel { } 

Mapper.CreateMap<Entity, ViewModel>() 
    .Include<AEntity, AViewModel>() 
    .Include<BEntity, BViewModel>(); 

// Then map AEntity and BEntity as well. 

所以，除非你有这种情况，.Include是不正确的使用。

我认为最好的方法是使用ConstructUsing：

Mapper.CreateMap<AuditVm, CardBase>(); 

Mapper.CreateMap<AuditVm, SetNewCardSettings>() 
    .ConstructUsing(src => 
      { 
       SetNewCardSettings settings = new SetNewCardSettings(); 
       Mapper.Map<AuditVm, CardBase>(src, settings); 
       return settings; 
      }) 
    .IgnoreUnmappedProperties(); 

Mapper.CreateMap<CreateCardVm, SetNewCardSettings>() 
    .ConstructUsing(src => Mapper.Map<SetNewCardSettings>(src.Audit)) 
    .IgnoreUnmappedProperties(); 

我还加入this answer's扩展方法忽略所有未映射属性。由于我们使用的是ConstructUsing，AutoMapper并不知道我们已经处理了这些属性。

更新小提琴：https://dotnetfiddle.net/6ZfZ3z