ExplicitMapper

An explicit object mapper pattern for C#/.NET

Motivation

• Better developer experience

  • Easily navigate to the mapping method implementation from the calling side
  • Autocomplete available target types based on the mapping source

• Support for multiple mappings for the same source/target type pair

• Compared to convention-based mappers, renaming a source/target property won't silently break anything

  "There are a lot of complex objects with many properties in my project, it would require too much time to map them manually"

You can use the Mapping Generator extension that will generate the corresponding mapping methods for you.

  "I would prefer the convention-based approach instead of the mapping methods for most of my objects"

You can still have it - add an ExplicitMapper constructor with the AutoMapper's IMapper parameter, pass it down to the ExplicitMapperFromSource and use it to implement ToTarget() mapping methods:

public partial class ExplicitMapper
{
    private readonly IMapper _mapper;

    public ExplicitMapper(IMapper mapper)
    {
        _mapper = mapper;
    }
}

public partial class ExplicitMapper
{
    public ExplicitMapperFromSource Map(Source source) => new(_mapper, source);
}

public partial class ExplicitMapperFromSource
{
    private readonly IMapper _mapper;
    private readonly Source _source;

    public ExplicitMapperFromSource(IMapper mapper, Source source)
    {
        _mapper = mapper;
        _source = source;
    }
}

public partial class ExplicitMapperFromSource
{
    public Target ToTarget() => _mapper.Map<Target>(_source);
}