有没有一种方法告诉AutoMapper忽略所有的属性,除了那些显式映射的?

我有可能从外部更改的外部DTO类,并且我希望避免显式地指定要忽略的每个属性,因为添加新属性将在尝试将它们映射到自己的对象时破坏功能(导致异常)。


当前回答

默认情况下,AutoMapper使用目标类型来验证成员,但您可以通过使用MemberList跳过验证。没有选择。

var configuration = new MapperConfiguration(cfg =>
  cfg.CreateMap<Source2, Destination2>(MemberList.None);
);

你可以在这里找到参考资料

其他回答

这似乎是一个老问题,但我想我会把我的答案贴出来给那些长得像我的人。

我使用ConstructUsing,对象初始化器加上ForAllMembers忽略例如

    Mapper.CreateMap<Source, Target>()
        .ConstructUsing(
            f =>
                new Target
                    {
                        PropVal1 = f.PropVal1,
                        PropObj2 = Map<PropObj2Class>(f.PropObj2),
                        PropVal4 = f.PropVal4
                    })
        .ForAllMembers(a => a.Ignore());

您希望如何指定忽略某些成员?是否有您想要应用的约定、基类或属性?一旦您开始显式地指定所有映射,我不确定您能从AutoMapper中得到什么价值。

从AutoMapper 5.0开始,IMappingExpression上的. typemap属性消失了,这意味着4.2解决方案不再有效。我已经创建了一个解决方案,使用原始功能,但具有不同的语法:

var config = new MapperConfiguration(cfg =>
{
    cfg.CreateMap<Src, Dest>();
    cfg.IgnoreUnmapped();        // Ignores unmapped properties on all maps
    cfg.IgnoreUnmapped<Src, Dest>();  // Ignores unmapped properties on specific map
});

// or add  inside a profile
public class MyProfile : Profile
{
   this.IgnoreUnmapped();
   CreateMap<MyType1, MyType2>();
}

实现:

public static class MapperExtensions
{
    private static void IgnoreUnmappedProperties(TypeMap map, IMappingExpression expr)
    {
        foreach (string propName in map.GetUnmappedPropertyNames())
        {
            if (map.SourceType.GetProperty(propName) != null)
            {
                expr.ForSourceMember(propName, opt => opt.Ignore());
            }
            if (map.DestinationType.GetProperty(propName) != null)
            {
                expr.ForMember(propName, opt => opt.Ignore());
            }
        }
    }

    public static void IgnoreUnmapped(this IProfileExpression profile)
    {
        profile.ForAllMaps(IgnoreUnmappedProperties);
    }

    public static void IgnoreUnmapped(this IProfileExpression profile, Func<TypeMap, bool> filter)
    {
        profile.ForAllMaps((map, expr) =>
        {
            if (filter(map))
            {
                IgnoreUnmappedProperties(map, expr);
            }
        });
    }

    public static void IgnoreUnmapped(this IProfileExpression profile, Type src, Type dest)
    {
        profile.IgnoreUnmapped((TypeMap map) => map.SourceType == src && map.DestinationType == dest);
    }

    public static void IgnoreUnmapped<TSrc, TDest>(this IProfileExpression profile)
    {
        profile.IgnoreUnmapped(typeof(TSrc), typeof(TDest));
    }
}

我已经能够做到这一点的方式如下:

Mapper.CreateMap<SourceType, DestinationType>().ForAllMembers(opt => opt.Ignore());
Mapper.CreateMap<SourceType, DestinationType>().ForMember(/*Do explicit mapping 1 here*/);
Mapper.CreateMap<SourceType, DestinationType>().ForMember(/*Do explicit mapping 2 here*/);
...

注意:我使用的是AutoMapper v.2.0。

The only infromation about ignoring many of members is this thread - http://groups.google.com/group/automapper-users/browse_thread/thread/9928ce9f2ffa641f . I think you can use the trick used in ProvidingCommonBaseClassConfiguration to ignore common properties for similar classes. And there is no information about the "Ignore the rest" functionality. I've looked at the code before and it seems to me that will be very and very hard to add such functionality. Also you can try to use some attribute and mark with it ignored properties and add some generic/common code to ignore all marked properties.