AutoMapper - Map List to HashSet

Question

I want to map my DTO to an entity. The only difference between the two is my dto's use List as collection type and the entities use HashSet. How can I configure Automapper to automatically map to a HashSet when it encounters an ICollection? Currently it just replaces the hashset in the entity with a List.

Example classes and mapping:

cfg.CreateMap<MachineDto, Machine>(MemberList.Source)
cfg.CreateMap<Machine, MachineDto>(MemberList.Destination)

public class Machine
{
    public Machine()
    {
        Segment = new HashSet<Segment>();
    }

    public long ID { get; set; }    
    public string Name { get; set; }            
    public ICollection<Segment> Segment { get; set; }
}


public class Segment
{
    public Segment()
    {        

    }

    public long ID { get; set; }
    public long MachineID { get; set; }
    public string Serial { get; set; }
}


public class MachineDto
{
    public MachineDto()
    {
        Segment = new List<SegmentDto>();
    }

    public long ID { get; set; }    
    public string Name { get; set; }            
    public ICollection<SegmentDto> Segment { get; set; }
}


public class SegmentDto
{
    public SegmentDto()
    {        

    }

    public long ID { get; set; }
    public string Serial { get; set; }
}

Answer 1

After a lot of fiddling around with the AfterMap() I found the UseDestinationValue option, when defined it will reuse the existing HashSet instead of replacing the ICollection with a List.

cfg.CreateMap<MachineDto, Machine>(MemberList.Source)
.ForMember(dest => dest.Segment, opt => opt.UseDestinationValue());