使用CustomResolver

以下是一个示例，演示如何在Automapper使用CustomResolver解决这个问题：

public class Source
{
    public List Values { get; set; }
}

public class Destination
{
    public List Values { get; set; }
}

public class ListResolver : IValueResolver>
{
    public List Resolve(Source source, Destination destination, List destMember, ResolutionContext context)
    {
        if (destMember == null)
            return source.Values;

        return destMember;
    }
}

// 配置Automapper映射
var config = new MapperConfiguration(cfg =>
{
    cfg.CreateMap()
        .ForMember(dest => dest.Values, opts => opts.UseDestinationValue())
        .ForMember(dest => dest.Values, opts => opts.ResolveUsing());
});

// 执行映射
var source = new Source { Values = new List { 1, 2, 3 } };
var destination = new Destination { Values = new List { 4, 5 } };
var mapper = config.CreateMapper();
mapper.Map(source, destination);

// destination.Values 现在应该是[4, 5, 1, 2, 3]