How to work with multiple database connection and repository pattern - asp.net-mvc

Question

I have a c# project with EF and repository pattern.
For single database everything work's fine but I have different model which are related to different database like User model data are come from control panel database and other model are also come from different database.
Here I use common repository pattern for the project. Now how can I send the database connection string to the repository when I initialize the model?
Here is my repository pattern :
public class Repository<C,T> : IRepository<T> where T : class where C : DbContext, new()
{
private C _context = new C();
public C context
{
get
{
//if (_context == null)
//{
// _context = new C();
// _context.Database.Connection.ConnectionString = "the new connectionstring";
//}
//return dataContext;
return _context;
}
set { _context = value; }
}
private IDbSet<T> _entities;
private IDbSet<T> Entities
{
get
{
if (_entities == null)
_entities = context.Set<T>();
return _entities;
}
}
And this is my Service class
public class UserService: Repository<DyeingContext,User> , IUserRepository
{
public UserService()
{
DyeingContext d = new DyeingContext(DataBase.ControlPanal);
}
//private readonly IRepository<User> _useRepository = new Repository<User>(new DyeingContext(DataBase.ControlPanal));
}``
and here is my context class
public partial class DyeingContext:DbContext
{
public DyeingContext(string pDbName):base(GetTheContext(pDbName))
{
}
public DyeingContext():base()
{
//throw new NotImplementedException();
}
public static string GetTheContext(string pDbName)
{
return ConnectionSettings.GetConnectionStringByDbName(pDbName);
}
}
I cant get the connection string in here
DyeingContext d = new DyeingContext(DataBase.ControlPanal);
it says
database connection through exception of type system.argumentexception
Is there a way to pass the multiple connections strings to the repository?
How and where I should initialize my connection string and how I pass it through rerpository?

Answer 1

I am not sure if you received your answer from the above comments. But here is how i would implement that.
1- Create a dbContext concrete class for each database. Both inheriting from EF DbContext.
2- In config file, create a connection string key for each database. This key is then supplied to each dbContext class as ctr param. As follows:
public DB1Context()
: base("db1") // connection string key
{
this.Configuration.LazyLoadingEnabled = false;
this.Configuration.ProxyCreationEnabled = false;
}
public DB2Context()
: base("db2") // connection string key
{
this.Configuration.LazyLoadingEnabled = false;
this.Configuration.ProxyCreationEnabled = false;
}
3- Each database must have its own repositories. For instance, AccountRepository inherits from the base repository. Its db context is supplied on contructor init as follows.
public class AccountRepository : DataRepositoryBase<Account>, IAccountRepository
{
private DB1Context db1Context = new DB1Context();
public AccountRepository()
{
this.DBContext = db1Context;
}
}
This way, you can communicate with multiple databases through its repositories. The same engine / service can inject repositories from different databases.