表达式必须解析为 top-level 成员而不是任何 child object 的属性

Expression must resolve to top-level member and not any child object's properties

我正在尝试将具有复杂结构的 object 映射到简单的 object:

 public class Contact
{
    public string ContactName { get; set; }
    public IEnumerable<Phone> Phones { get; set; }
}
public class Phone
{
    public string Number { get; set; }
    public PhoneType Type { get; set; }
}


public enum PhoneType
{
    Phone,
    Mobile
}

public class ContactDto
{
    public string ContactName { get; set; }
    public string PhoneNumber { get; set; }
    public string MobileNumber { get; set; }
}

 Mapper.CreateMap<ContactDto, Contact>()
                .ForMember(p => p.Phones.FirstOrDefault(k => k.Type.Equals(PhoneType.Mobile)).Number, r => r.MapFrom(s => s.MobileNumber))
                .ForMember(p => p.Phones.FirstOrDefault(k => k.Type.Equals(PhoneType.Phone)).Number, r => r.MapFrom(s => s.PhoneNumber));

但是我的标题有误。怎么了?

您的通用参数顺序错误。源应该是第一个,目的地是后者。

试试这个:

Mapper.CreateMap<Contact, ContactDto>()
       .ForMember(dto => dto.PhoneNumber, dto => dto.MapFrom(src => src.Phones.First(p => p.Type == PhoneType.Phone).Number))
       .ForMember(dto => dto.MobileNumber, dto => dto.MapFrom(src => src.Phones.First(p => p.Type == PhoneType.Mobile).Number));