自动映射器映射到可为null的DateTime属性

Question

使用Automapper 3.1.1，我无法编译此映射：

Mapper.CreateMap<Domain.DomainObjects.Entities.Patient, PatientDto>()
                .ForMember(x => x.Deleted, opt => opt.MapFrom(input => input.Deleted.HasValue ? 
                    new DateTime(input.Deleted.Value.Ticks, DateTimeKind.Utc) : null ));

错误：

Type of conditional expression cannot be determined because there is no implicit conversion between '<null>' and 'DateTime'

实体：

public class Patient : Entity
{
        // more properties
        public virtual DateTime? Deleted { get; set; }
}

感觉像我遗漏了一些明显的东西，但无法弄清楚到底是什么。

注意：Dto包含DateTime? Deleted DateTime? Deleted了

Answer 1

我尚未测试，但是您只需要显式将null转换为DateTime? 。 （ (DateTime?)null ）

Mapper.CreateMap<Domain.DomainObjects.Entities.Patient, PatientDto>()
                .ForMember(x => x.Deleted, opt => opt.MapFrom(input => input.Deleted == null ? (DateTime?)null : (
                new DateTime(input.Deleted.Value.Ticks, DateTimeKind.Utc))));

Answer 2

只需将新的DateTime为DateTime? ：

Mapper.CreateMap<Domain.DomainObjects.Entities.Patient, PatientDto>()
            .ForMember(x => x.Deleted, opt => opt.MapFrom(input => input.Deleted.HasValue ? 
                (DateTime?) new DateTime(input.Deleted.Value.Ticks, DateTimeKind.Utc) : null ));