Question

I have this line of code in my global.asax

Mapper.CreateMap<Order, OrderDTO>();

These are my classes:

public class Customer
    {
        public string Name {get; set;}
    }
    public class Order
    {
        public int OrderId { get; set; }
        public Customer Customer { get; set; }
    }

    public class OrderDTO
    {
        public int OrderId { get; set; }
        public string Name { get; set; }

    }

And this is my code:

Customer cust = new Customer { Name = "Jaggu" };

Order order = new Order { Customer = cust, OrderId = 123 };

OrderDTO dto = Mapper.Map<Order,OrderDTO>(order);

my dto contains OrderId but Name is null. As per documentation it should work:

https://github.com/AutoMapper/AutoMapper/wiki/Flattening

If I change my global.asax’s mapping to this:

Mapper.CreateMap<Order, OrderDTO>().ForMember(dest => dest.Name, 
       mapping => mapping.MapFrom(order => order.Customer.Name));

it works! This make me curious. Is the doc wrong? or am I doing it wrong?

Answer 1

It will work if you follow the standard naming convention:

public class OrderDTO
{
    public int OrderId { get; set; }
    public string CustomerName { get; set; }
}

Notice that the property is called CustomerName and not Name. When flattening the Order model into a Dto, the Customer.Name goes into CustomerName.