AutoMapper : Map both ways in Net Core 2 syntax

Question

What is syntax to map both ways in AutoMapper Net Core2? I need to map ProductViewModel and ProductDto both ways. This is not working,

Startup.cs

var config = new MapperConfiguration
(
    cfg => cfg.CreateMap<Models.ProductDto, Models.ProductViewModel>(),
    cfg => cfg.CreateMap<Models.ProductViewModel, Models.ProductDto>()
);

var mapper = config.CreateMapper();

Answer 1

I'd rather create a seprate initializer and mapper. e.g here is my AutoMapperStartupTask class.

public static class AutoMapperStartupTask
{
    public static void Execute()
    {
        Mapper.Initialize(
            cfg =>
            {
                cfg.CreateMap<ProductViewModel, ProductDto>()
                    .ReverseMap();
            });
    }
}

And Mapper

public static class DtoMapping
{
    public static ProductViewModel ToModel(this ProductDto dto)
    {
        return Mapper.Map<ProductDto, ProductViewModel>(dto);
    }

    public static ProductDto ToDto(this ProductViewModel dto)
    {
        return Mapper.Map<ProductViewModel, ProductDto>(dto);
    }
}

Startup.cs

public void ConfigureServices(IServiceCollection services)
{
   AutoMapperStartupTask.Execute();
}

Use in Controller

var dto = productModel.ToDto();
var model = productDto.ToModel();