BatMap - The Mapper we deserve, not the one we need.

🦇 BatMap Opininated (yet another) mapper, mainly to convert between EF Entities and DTOs.

Supports .Net Standard 1.0.

Let’s first obey the number one rule for mappers, a benchmark (using BenchmarkDotNet):

Method	Mean
HandWritten	1.143 ms
BatMap	2.000 ms
SafeMapper	2.933 ms
Mapster	2.942 ms
AutoMapper	3.497 ms
TinyMapper	4.172 ms
ExpressMapper	6.955 ms
FastMapper	9.203 ms

^{Results may (probably) vary. Latest run can bee seen on Appveyor Build.}

Fast (enough)
NOT over-engineered, code is really simple
Instantiatable mapper
Convention based, zero configuration static shortcut exists too (obviously named Mapper)
Does not crash when faced with circular-dependencies during registration
In fact, can resolve recurring instances to same target instance (yaay no StackOverflowException!)
Can project IQueryable<TSource> to IQueryable<TTarget> with respect to includes (via auto-detection or with custom parameters)
and much more…

API

Registration with static API:

Mapper.RegisterMap<Customer, CustomerDTO>();

or use an instance:

var mapper = new MapConfiguration(dynamicMapping: DynamicMapping.MapAndCache, preserveReferences: true);
mapper.RegisterMap<Customer, CustomerDTO>();

Note: You don’t have to register type mappings when using a MapConfiguration with Dynamic Mapping enabled (like the static API uses).

You can customize expressions for members:

mapper.RegisterMap<Order, OrderDTO>(b => b.MapMember(o => o.Price, (o, mc) => o.Count * o.UnitPrice));

Map an object:

Mapper.Map<CustomerDTO>(customer);

Map an enumerable:

customers.MapTo<Customer, CustomerDTO>(preserveReferences: true);  // extension methods FTW!

Project a query:

customerQuery.ProjectTo<CustomerDTO>(checkIncludes: true);

or with expanding specific navigations:

customerQuery.ProjectTo<Customer, CustomerDTO>(c => c.Addresses, c => c.Orders);

Note: If you want to change mapping behavior, create a class that inherits from ExpressionProvider, override CreateMemberBinding and inject an instance of your class to MapConfiguration.

Where can I get it?

You can install BatMap from the package manager console:

PM> Install-Package BatMap

Documentation

You might want to visit wiki for more.

Developed with at Doğuş Teknoloji.