Automapper custom inline mapping

Question

I have two classes

 public class SourceClass
{
    public Guid Id { get; set; }
    public Guid Provider { get; set; }
}


public class DestinationClass
{
    public Guid Id { get; set; }
    public Guid Provider { get; set; }
    public Guid CustomerId {get; set;}
}

I've initialized my mapping by using the following code

CreateMap<SourceClass, DestinationClass>();

And then in my controller, I have :

Mapper.Map<List<DestinationClass>>(requests)

where "requests" is a List of SourceClass objects being passed in to my controller.

Now, this code works and the mapping works as configured. However, I also get passed a CustomerId and want to set it in the DestinationClass accordingly.

Is there any way to do this while the mapping is occuring, so that I don't have to write an additional loop to set CustomerId in every object in the list?

Answer 1

You can pass additional parameter by passing key-value to mapper (as suggested by @LucianBargaoanu). The custom value resolver and map execution can be implemented as:

// Configuration 
var configuration = new MapperConfiguration(cfg =>
{
    cfg.CreateMap<SourceClass, DestinationClass>()
      .ForMember(dest => dest.CustomerId, opt => 
      opt.MapFrom((src, dest, destMember, context) =>
      context.Items["CustomerId"]));
});

var mapper = configuration.CreateMapper();

//Sample source class
var sourceClass = new SourceClass { Id = Guid.NewGuid(), Provider = Guid.NewGuid() };

var destClass = mapper.Map<SourceClass, DestinationClass>(sourceClass,
              opt => opt.Items["CustomerId"] = "96b4b6e6-7937-4579-ba01-4a051bc0b93b");

The CustomerId member of destClass object is populated with passed GUID.

Note:SourceClass and DestinationClass definition are taken from OP.