CreateMapSaveMaterialDto Material ForMemberdest = destId opt = optIgnore ForAllMembersopt = optConditionsrc dest srcMember destMember = srcMember != null && srcMemberGetTypeIsValueType srcMembe

尝试使用以下代码来进行判断值类型为NULL映射为NULL：

CreateMap<SaveMaterialDto, Material>() .ForMember(dest => dest.Id, opt => opt.Ignore()) .ForAllMembers(opt => opt.Condition((src, dest, srcMember, destMember, context) => { if (srcMember != null && srcMember.GetType().IsValueType) { return !srcMember.Equals(Activator.CreateInstance(srcMember.GetType())); } return srcMember != null; }));