entity framework - C#/EF and the Repository Pattern: Where to put the ObjectContext in a solution with multiple repositories? -

i have multiple repositories in application. should put objectcontext? right now, have reference objectcontext ctx; in every repository. smartest , safest way go this?

a design multiple objectcontext instances acceptable if repository methods commit transaction. otherwise, possible external calls commit transaction may not persist intend, because hold references different instances of objectcontext.

if want restrict objectcontext single instance, can build repositoryprovider class contains objectcontext, , manages propagation of repository actions data commits. can best accomplished either, - injecting objectcontext reference each repository, or - subscribing repositories' events eventhandlers call appropriate methods on objectcontext.

the following highly pluggable implementation have used:

repository provider interface

public interface irepositoryprovider {     irepository this[type repositorytype] { get; } } 

repository factory interface

the implementation has dependency on ienumerable<ifilteredrepositoryfactory>.

public interface ifilteredrepositoryfactory{    bool cancreaterepository(type repositorytype);    irepository createrepository(type repositorytype, objectcontext context); } 

so, implementation looks like:

repository provider class

public class repositoryprovider {     public repositoryprovider(objectcontext context, ienumerable<ifilteredrepositoryfactory> repositoryfactories)     {         _context = context;         _repositoryfactories = repositoryfactories;     }      private readonly objectcontext _context;     private readonly ienumerable<ifilteredrepositoryfactory> _repositoryfactories;     private readonly dictionary<type, irepository> _loadedrepositories;      irepository this[type repositorytype]     {                 {             if(_loadedrepositories.containskey(repositorytype))             {                 return _loadedrepositories[repositorytype];             }             var repository = getfactory(repositorytype).createrepository(repositorytype, _context);             _loadedrepositories.add(repositorytype,repository);             return repository;         }     }      ifilteredrepositoryfactory getfactory(type repositorytype)     {         //throws exception if no repository factory found         return _repositoryfactories.first(x => x.cancreaterepository(repositorytype));     } } 

it should noted new repository created first matching factory implementation. so, if collection of factories contains multiple factories can create repository given repository type, first ifilteredrepositoryfactory object in enumerable used , subsequent factories ignored. in addition, if there no registered factory, , exception thrown.