I'm trying to make a plug in that will use EF6.1 and SQLite for an app where I can't change the App.config so all the configuration and connection string needs to be set in code.
I found this answer that looked promising Problems using Entity Framework 6 and SQLite
So now I have a configuration class like this:
public class CollectionDbConfiguration : DbConfiguration { public CollectionDbConfiguration() { SetProviderServices("System.Data.SQLite"(DbProviderServices)SQLiteProviderFactory.Instance.GetService(typeof(DbProviderServices))); SetProviderFactory("System.Data.SQLite.EF6", SQLiteProviderFactory.Instance); SetProviderFactory("System.Data.SQLite", SQLiteFactory.Instance); } } I have confirmed this gets hit before the context is created for the first time and all these return values.
My context looks like this
public class MyContext : DbContext { public MyContext(string connectionString) : base(connectionString) { } public DbSet<MyEntity> MyEntities { get; set; } } And I have some code calling it like this:
var context = new MyContext("Data Source = mytest.db; Version = 3;"); var entities = context.MyEntities.ToList(); When I try and run the code it looks like the context is assuming the connection string is for SQL Server as it gives me:
Keyword not supported: 'version'.
If I remove it I then get an error that it cannot connect and its clearly trying to connect to a SQL Server database.
I tried passing in a SQLite connection by adding a constructor:
public MyContext(DbConnection connection) : base(connection, contextOwnsConnection: true) { } And calling it with this:
var context = new MyContext(new SQLiteConnection("Data Source = mytest.db; Version = 3;")); var entities = context.MyEntities.ToList(); But then I get the error:
Unable to determine the DbProviderFactory type for connection of type 'System.Data.SQLite.SQLiteConnection'. Make sure that the ADO.NET provider is installed or registered in the application config.
So I made a factory resolver and registered that
public class FactoryResolver : IDbProviderFactoryResolver { public DbProviderFactory ResolveProviderFactory(DbConnection connection) { if (connection.GetType() == typeof(SQLiteConnection)) { return SQLiteFactory.Instance; } if (connection.GetType() == typeof(EntityConnection)) { return SQLiteProviderFactory.Instance; } return null; } } And added:
SetProviderFactoryResolver(new FactoryResolver()); but now I get this:
No Entity Framework provider found for the ADO.NET provider with invariant name 'System.Data.SQLite.EF6'. Make sure the provider is registered in the 'entityFramework' section of the application config file. See http://go.microsoft.com/fwlink/?LinkId=260882 for more information.
I've beet at this for two days now and I'm running out of ideas.
1 Answers
Answers 1
The minimum needed to make the constructor with connection string working is a custom IProviderInvariantName, IDbDependencyResolver and DbConfiguration:
public class SQLiteProviderInvariantName : IProviderInvariantName { public static readonly SQLiteProviderInvariantName Instance = new SQLiteProviderInvariantName(); private SQLiteProviderInvariantName() { } public const string ProviderName = "System.Data.SQLite.EF6"; public string Name { get { return ProviderName; } } } class SQLiteDbDependencyResolver : IDbDependencyResolver { public object GetService(Type type, object key) { if (type == typeof(IProviderInvariantName)) return SQLiteProviderInvariantName.Instance; if (type == typeof(DbProviderFactory)) return SQLiteProviderFactory.Instance; return SQLiteProviderFactory.Instance.GetService(type); } public IEnumerable<object> GetServices(Type type, object key) { var service = GetService(type, key); if (service != null) yield return service; } } class SQLiteDbConfiguration : DbConfiguration { public SQLiteDbConfiguration() { AddDependencyResolver(new SQLiteDbDependencyResolver()); } } Now this should work:
var context = new MyContext("Data Source = mytest.db; Version = 3;"); var entities = context.MyEntities.ToList(); Update: For NET4.0 you would also need a custom IDbProviderFactoryResolver:
class SQLiteDbProviderFactoryResolver : IDbProviderFactoryResolver { public static readonly SQLiteDbProviderFactoryResolver Instance = new SQLiteDbProviderFactoryResolver(); private SQLiteDbProviderFactoryResolver() { } public DbProviderFactory ResolveProviderFactory(DbConnection connection) { if (connection is SQLiteConnection) return SQLiteProviderFactory.Instance; if (connection is EntityConnection) return EntityProviderFactory.Instance; return null; } } and add
if (type == typeof(IDbProviderFactoryResolver)) return SQLiteDbProviderFactoryResolver.Instance; to the SQLiteDbDependencyResolver.GetService method implementation.
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