Question

Why do I have to call the .CreateMap method?

Actually its totally obviously that calling the .Map method has the same source/destination parameter.

Is this a typical case “if you dont like the software do not use it”

or is there an easier less cumbersome way to make a mapping in one line I do not know of?

Mapper.CreateMap<ReleaseViewModel, Release>();
Release release = (Release)Mapper.Map(releaseViewModel, typeof(ReleaseViewModel), typeof(Release));

Answer 1

I think you can see the “CreateMap<>” as method to register your mapping with automapper.
The “Map()” is actualy executing the mapping registered.

The “CreateMap<>” has extra methods to fine grain your mapping, which is by itself a reason to seperate those two methods. Think of it as “Seperation of Concern”-principle.

One liner wrapper

public abstract class Mapper<TFrom, TTo>
{
    private void Configure()
    {
        Mapper.CreateMap<TFrom, TTo>();
    }

    public TTo Map(TFrom @from)
    {
        Configure();
        return Mapper.Map<TFrom, TTo>(@from);
    }

    public IEnumerable<TTo> Map(IEnumerable<TFrom> fromList)
    {
        return fromList == null
            ? null 
            : fromList.Select(Map).ToList();
    }
}