c# - AutoMapper - 如何在自定义类型转换器中使用自定义值解析器

Question

如何在自定义类型转换器中使用自定义值解析器？ 目前，在我看来很难实现。您知道我如何使用该类(class)的方法吗？

---

人物转换器

class PersonConverter : ITypeConverter<PersonData, Person>
{
    public Person Convert(ResolutionContext context)
    {
        var personData = context.SourceValue as PersonData;
        if (personData == null)
        {
            return null;
        }

        var person = new Person
        {
            Name = personData.Name
        };
        //person.Dic = // use here my DictionaryResolver

        return person;
    }
}

型号

class Person
{
    public string Name { get; set; }
    public Dictionary Dic { get; set; }
}

class PersonData
{
    public string Name { get; set; }
    public int DicId { get; set; }
}

class Dictionary
{
    public int Id { get; set; }
    public string Name { get; set; }
}

值(value)解析器

class DictionaryResolver : ValueResolver<int, Dictionary>
{
    protected override Dictionary ResolveCore(int source)
    {
        // do something
        return new Dictionary
        {
            Id = source,
            Name = "Name"
        };
    }
}

Answer 1

自定义值解析器设计用于在 AutoMapper 将要映射对象时覆盖特定成员的映射:

Mapper.CreateMap<PersonData, Person>()
                .ForMember(dest => dest.Dic, opt => opt.ResolveUsing<DictionaryResolver>());

但是，当您使用自定义类型解析器时，这会完全控制映射:无法自定义某个特定成员的映射方式:

Mapper.CreateMap<TPersonData, Person>().ConvertUsing(PersonConverter ); // No ForMember here.

但是，鉴于您在类型转换期间拥有完全控制权，没有什么可以阻止您重用值转换器，您只需要具体引用它:但是您必须添加一个公共(public)方法它返回 protected 方法 ResolveCore:

class DictionaryResolver : ValueResolver<int, Dictionary>
{
    public Dictionary Resolve(int source)
    {
        return ResolveCore(source);
    }

    protected override Dictionary ResolveCore(int source)
    {
        // do something
        return new Dictionary
        {
            Id = source,
            Name = "Name"
        };
    }
}

然后在类型转换期间调用它来解析该属性:

var person = new Person
    {
        Name = personData.Name
    };

DictionaryResolver resolver = new DictionaryResolver();
person.Dic = resolver.Resolve(personData.IntValue); // whatever value you use