Automapper: map properties manually

Question

I just started to use automapper to map DTOs<->Entities and it seems to be working great.

In some special cases I want to map only some properties and perform additio

Answer 1

If you just want to map only some select property than you have to do as below

// Create a map
var map = CreateMap<Source,Target>();
// ingnore all existing binding of property
map.ForAllMembers(opt => opt.Ignore());
// than map property as following
map.ForMember(dest => dest.prop1, opt => opt.MapFrom( src => src.prop1));
map.ForMember(dest => dest.prop2, opt => opt.MapFrom( src => src.prop2));

Answer 2

You can make some projection using MapFrom method - http://automapper.readthedocs.io/en/latest/Projection.html

Mapper.Map(source, target)
   .ForMember(m => m.Property, opt => opt.MapFrom(src => src.ChangedProperty));

For example (reffering to AutoMapper documentation):

// Model
var calendarEvent = new CalendarEvent
    {
        Date = new DateTime(2008, 12, 15, 20, 30, 0),
        Title = "Company Holiday Party"
    };

// Configure AutoMapper
Mapper.CreateMap<CalendarEvent, CalendarEventForm>()
    .ForMember(dest => dest.EventDate, opt => opt.MapFrom(src => src.Date.Date))
    .ForMember(dest => dest.EventHour, opt => opt.MapFrom(src => src.Date.Hour))
    .ForMember(dest => dest.EventMinute, opt => opt.MapFrom(src => src.Date.Minute));

Answer 3

If I read your question correctly, yes, as long as your destination (target) property matches your conversion.

So if I am going from a string to a bool for a Status of "A" or "I" (active/inactive), I can do something like:

.ForMember(dest => dest.Status, opt => opt.MapFrom(src => src.Status == "A"))

And then when going the other direction, convert it back:

.ForMember(dest => dest.Status, opt => opt.MapFrom(src => src.Status ? "A" : "I"))

A date example:

.ForMember(dest => dest.SomeDate, opt => opt.MapFrom(src => src.SomeDate.ToString("M/d/yyyy")));