价值注入:Dto到域模型(NHibernate)

Question

我正在使用ValueInjecter将属性从域模型映射到通过服务层提供的DTO.有问题的服务也接受更新...因此传入更新的DTO,然后将其注入域对象并保存.

    // Domain
    public class Member 
    {
      public Country Country { get; set; }
    }

    public class Country 
    {
      public string Code { get; set; }
      public string Name { get; set; }
    }

    //Dto
    public class MemberDto 
    {
       public string CountryCode { get; set; }
    }

    //Transformation Method attempt 1
    public Member InjectFromDto (MemberDto dto, Member source)
    {
       source = source.InjectFrom<UnflatLoopValueInjection>(dto);
       return source;
    }

现在所有上面的代码都更新了Property Member.Country.Code,这显然不是我需要它做的.

所以从文档中,我想我需要创建一个覆盖并得到这个:

public class CountryLookup: UnflatLoopValueInjection<string, Country>
    {
        protected override Country SetValue(string sourcePropertyValue)
        {
            return countryService.LookupCode(sourcePropertyValue);
        }
    }


 //revised transformation call
 //Transformation Method attempt 2
    public Member InjectFromDto (MemberDto dto, Member source)
    {
       source = source.InjectFrom<UnflatLoopValueInjection>(dto)
                      .InjectFrom<CountryLookup>(dto);
       return source;
    }

我的问题是在调试期间,CountryLookup永远不会被调用.

我能想到的可能原因:

• Nhibernate Proxy类导致值injecter与Country类型不匹配？这没有意义,因为它在扁平化过程中起作用.
• 也许由于某种原因,不平息不会被解雇.即Dto是CountryCode,Domain是Country.Code

我需要使用Dto上的CountryCode属性来调用countryService.LookupCode以返回在更新注入期间使用的正确对象.

Answer 1

使用 Omu 的建议/参考，这是问题的具体代码。

 public class CountryLookup : ExactValueInjection
    {
        private ICountryService countryservice;

        public CountryLookup(ICountryService countryService)
        {
           this.countryService = countryService; 
        }

        protected override bool TypesMatch(Type s, Type t)
        {
            return (s == typeof(string)) && (t == typeof (Country));

        }
        protected override Object SetValue(object v)
        {
            if (v == null) 
                return null;

            var country = countryService.LookupCode((string) v);
            return country;
        }

        public override string SourceName()
        {
            return "CountryCode";
        }

        public override string TargetName()
        {
            return "Country";
        }    
    }

public Member InjectFromDto (MemberDto dto, Member source)
{
   source = source.InjectFrom<UnflatLoopValueInjection>(dto)
                  .InjectFrom<CountryLookup>(dto);
   return source;
}