default DbConfiguration instance was used by EntityFramework

Emanuele Leoni

I have a DAL project with this ApplicationContext.cs

[DbConfigurationType(typeof(MyConfiguration))]
public class ApplicationDbContext : IdentityDbContext
{
public ApplicationDbContext() : base("DefaultConnection", throwIfV1Schema: false) { } ...
}

but when I instance it in an other project

using (var databaseContext = new ApplicationDbContext()) { }

I get this error:

The default DbConfiguration instance was used by the Entity Framework before the 'MyConfiguration' type was discovered. An instance of 'MyConfiguration' must be set at application start before using any Entity Framework features or must be registered in the application's config file. See http://go.microsoft.com/fwlink/?LinkId=260883 for more information.

I tried to solve it updating the web.config file, inserting codeConfigurationType in node, but I get the same error.

Can anyone help me?

6 Replies

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Manav Pandya8y ago
Accepted answer
Hello

That's bcox you have provided correct assembly i think :

try another option like :
The second option is to place DbConfigurationTypeAttribute on your context class. For example:

[DbConfigurationType(typeof(MyDbConfiguration))]
public class MyContextContext : DbContext
{
}
Read instruction carefully :
https://msdn.microsoft.com/en-us/data/jj680699#Moving

Thanks
+1
Emanuele Leoni8y ago
Thank you Manav,
I solve updating my context class:

DbConfigurationType("MyNamespace.MyDbConfiguration, MyAssembly")]
public class MyContextContext : DbContext { }
0
Emanuele Leoni8y ago
Hello,
below the full snippet:

I think the error is in the codeConfigurationType

0
Manav Pandya8y ago
Hello

Make sure that you have added sql data provider in config file :
  "System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
And read description here :

https://msdn.microsoft.com/en-us/data/jj680699

https://social.msdn.microsoft.com/Forums/en-US/20c77828-3aa2-4519-822f-b563181a021d/entity-framework-configuration-doesnt-work?forum=adodotnetentityframework

Thanks
0
Emanuele Leoni8y ago
Hi Manav,
I tried changing web.config like this snippet:

but now I have this error:
The DbConfiguration type 'DAL.Context.MyConfiguration, DAL.Context' specified in the application config file could not be loaded. Make sure that the assembly-qualified name is used and that the assembly is available to the running application. See http://go.microsoft.com/fwlink/?LinkId=260883 for more information.
0
Manav Pandya8y ago
Hello

Have you tried below snippet in web.config ?

replace snippet of :

To
"MyProject.MyPackage.MyCustomDBConfiguration, MyProject.MyPackage">
    ...

For more reference you can follow forums below :
https://stackoverflow.com/questions/26361592/same-application-different-databases-entity-framework-6-x-mysql-sql-server

http://blog.jonschneider.com/2015/12/fix-default-dbconfiguration-instance.html

https://henrywrites.wordpress.com/2015/08/01/the-default-dbconfiguration-instance-was-used-by-the-entity-framework-before-the-sqlazureconfiguration-type-was-discovered/

I hope below links will sort out your doubts

Thanks
+1