c# - AutoMapper - 如何将参数传递给配置文件？

Question

我想使用自动映射器在我的公共(public)数据契约(Contract)和我的 BD 模型之间进行映射。我需要将一个字符串参数传递到我的 MapProfile 中，并从我的属性中获取描述(本例中为“代码”)。例如:

public class Source
{
    public int Code { get; set; }
}

public class Destination
{
    public string Description { get; set; }
}

public class Dic
{
    public static string GetDescription(int code, string tag)
    {
            //do something
            return "My Description";
    }
}

public class MyProfile : Profile
{

    protected override void Configure()
    {
        CreateMap<Destination, Source>()
            .ForMember(dest => dest.Description, 
                opt => /* something */ 
                Dic.GetDescription(code, tag));
    }
}

public class MyTest 
{

        [Fact]
        public void test()
        {
            var source = new Source { Code = 1};

            var mapperConfig = new MapperConfiguration(config => config.AddProfile<MyProfile>());
            var mapper = mapperConfig.CreateMapper();

            var result = mapper.Map<Destination>(source, opt => opt.Items["Tag"] = "AnyTag");

            Assert.Equal("My Description", result.Description);
        }
}

Answer 1

这可以使用 CustomResolver

来实现

public class MyProfile : Profile
{

    protected override void Configure()
    {
        CreateMap<Destination, Source>()
            .ForMember(dest => dest.Description, opt => opt.ResolveUsing<CustomResolver>().FromMember(src => src.Code));
    }
}

public class CustomResolver : IValueResolver
{
    public ResolutionResult Resolve(ResolutionResult source)
    {
        var code = (int)source.Value;

        var tag = source.Context.Options.Items["Tag"].ToString();

        var description = Dic.GetDescription(code, tag);

        return source.New(description);
    }
}