c# - Creating instance of a generic type from a instance of the type parameter -

i have bl consisting of generic repository , specific implementations couple of entity types (my dal entity framework 5 model). repository uses it's functionality method set() of system.data.entity.dbcontext. have expressions things getting siblings of entity t, these won't work on result of set(type entitytype).

at 1 moment have instance of non-generic dbentityentry. entity of type object. when use gettype() approptiate entity type. know want related entity using functions in repository. there way non-generic dbentityentry.

i tried:

public repository(t entity) {     \\ construction here } 

but repository<object> , call set<object> returns nothing expected.

i've searched way came empty.

take @ example posted george mauer in this thread. requires .net 4.0 or higher.

dynamic dynamiccast(object entity, type to) {     var opencast = this.gettype().getmethod("cast", bindingflags.static | bindingflags.nonpublic);     var closecast = opencast.makegenericmethod(to);     return closecast.invoke(entity, new[] { entity }); } static t cast<t>(object entity) t : object {     return entity t; } 

you can use modified variant of create matching repository instance:

public static dynamic createrepository(object entiry, type targettype) {     type basetype = typeof(repository<>);        type concretetype = basetype.makegenerictype(targettype);     var instance = activator.createinstance(concretetype, entiry);      return dynamiccast(instance, concretetype); }