AutoMapper是否支持从非泛型基类继承的Open Generics?

时间:2018-06-06 19:15:48

标签: c# automapper open-generics

AutoMapper版本#是7.0.0。

采取以下一组课程:

public class Person
{
    public string Name { get; set; }
    public List<BarBase> BarList { get; set; }
}

public class PersonModel
{
    public string Name { get; set; }
    public List<BarModelBase> BarList { get; set; }
}

abstract public class BarBase
{
    public int Id { get; set; }
}

public class Bar<T> : BarBase
{
    public T Value { get; set; }
}

abstract public class BarModelBase
{
    public int Id { get; set; }
}

public class BarModel<T> : BarModelBase
{
    public T Value { get; set; }
}

Person的属性BarList类型为List<BarBase>BarBase是一个抽象类,具有通用的具体实现Bar<T>;该列表需要包含多种类型的T

以下两种配置有效。注释掉的部分不按照评论中的说明工作。

var config = new MapperConfiguration(cfg =>
{
    cfg.CreateMap(typeof(BarBase), typeof(BarModelBase))
       .Include(typeof(Bar<string>), typeof(BarModel<string>));

    cfg.CreateMap(typeof(Bar<string>), typeof(BarModel<string>));
    cfg.CreateMap(typeof(Person), typeof(PersonModel));
});

var config = new MapperConfiguration(cfg =>
{
    //Fails with: System.NullReferenceException : Object reference not set to an instance of an object.
    //cfg.CreateMap(typeof(BarBase), typeof(BarModelBase)).As(typeof(BarModel<>));

    //Fails with:  Missing map from AutoMapper.UnitTests.OpenGenerics+Bar`1[T] to AutoMapper.UnitTests.OpenGenerics+BarModel`1[T]. Create using Mapper.CreateMap<Bar`1, BarModel`1>.
    //cfg.CreateMap(typeof(BarBase), typeof(BarModelBase))
    //   .Include(typeof(Bar<>), typeof(BarModel<>));

    cfg.CreateMap<BarBase, BarModelBase>().ConvertUsing((source, destination, context) =>
    {
        System.Type sourceType = source.GetType();
        System.Type structType = sourceType.GetGenericArguments()[0];

        return (BarModelBase)context.Mapper.Map(source, sourceType, typeof(BarModel<>).MakeGenericType(structType));
    });


    cfg.CreateMap(typeof(Person), typeof(PersonModel));
    cfg.CreateMap(typeof(Bar<>), typeof(BarModel<>));
});

验证任一配置是否有效:

Person person = new Person
{
    Name = "Jack",
    BarList = new List<BarBase>
    {
        new Bar<string>{ Id = 1, Value = "One" },
        new Bar<string>{ Id = 2, Value = "Two" }
    }
};

PersonModel personMapped = config.CreateMapper().Map<PersonModel>(person);

Assert.Equal("One", ((BarModel<string>)personMapped.BarList[0]).Value);

问题:我无法让AutoMapper的Open Generics适用于这种情况(Generic<T>扩展Non-Generic)而没有转换器(“ConvertUsing”)或显式映射每个封闭的泛型类型

问题:我错过了什么? - 我是否可以在不使用转换器的情况下使用开箱即用的类型映射配置?

1 个答案:

答案 0 :(得分:0)

AutoMapper issue log确认当前版本中此类映射需要转换器。