自动映射 - 当源对象具有值的属性时，不映射

Question

Our entities have a field called "DateDeleted". At times we might have these loaded into entities and we want to filter them out before sending them to the client.

Our Entities also have child entities which have child entities, all who have a DateDeleted.

What's the best practice to implement this with Automapper - Specifically - how can I map a Null value to the destination (for the entire object) when the source has a Date Deleted property with a value?

Answer 1

You can ignore a specific property when you configure your mappings

CreateMap<srcType, destType>.ForMember(x => x.DateDeleted, opt => opt.Ignore());

EDIT: To do custom conditional logic during the mapping you will need to implement a custom resolver:

public class NullCheckResolver : IValueResolver<TSrc, TDest, TProp>
{
    public TProp Resolve(TSrc source, TDest destination, TProp member, ResolutionContext context)
    {
        if (member.DateDeleted == null)
            return member;
        return null;
    }
}

CreateMap<TSrc, TDest>().ForMember(dest => dest.MyOptionalProperty, opt => opt.ResolveUsing<NullCheckResolver>());

For more details on custom resolvers, see the AutoMapper documentation