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My application needs to use a security dll. The security dll returns an OracleClient.OracleConnection object. I need to use this Connection object in my application. How do I make the DataContext use my Connection object?

The necessary connection (IDbConnection) could be passed to the DataContext constructor:
http://www.devart.com/linqconnect/docs/ ... _ctor.html
In this case a new instance of the DataContext class is initialized by referencing the connection used by the .NET Framework.

I tried using the constructor of the DataContext as below:

<ProviderAttribute(GetType(Devart.Data.Oracle.Linq.Provider.OracleDataProvider))> _
Partial Public Class DataContext
Inherits Devart.Data.Linq.DataContext

Public Sub New()
MyBase.New(GetConnection(), GetMappingSource())
OnCreated()
End Sub

Private Shared Function GetConnection() As System.Data.IDbConnection
'Function has code to get the connection (OracleClient.OracleConnection object)
End Function
End Class

I get the following error in the call to MyBase.New:
A first chance exception of type 'System.ArgumentException' occurred in Devart.Data.Linq.dll
<Message>Invalid connection type. Expected Type: System.Data.OracleClient.OracleConnection, Actual Type: Devart.Data.Oracle.OracleConnection</Message>
<StackTrace> at Devart.Data.Linq.Provider.DataProvider.Initialize(Object connection)
at Devart.Data.Oracle.Linq.Provider.OracleDataProvider.Initialize(Object connection)
at Devart.Data.Linq.Provider.DataProvider.Devart.Data.Linq.Provider.IProvider.Initialize(IDataServices dataServices, Object connection)
at Devart.Data.Linq.DataContext.a(Object A_0, MappingSource A_1, Type A_2)
at Devart.Data.Linq.DataContext..ctor(IDbConnection connection, MappingSource mapping)

I am using the OracleDataProvider as the provider. Is this correct. Do I need to write a custom provider? Any other suggestions?

I am using the OracleDataProvider as the provider. Is this correct. Do I need to write a custom provider? Any other suggestions?

Yes, to use a third-party data provider you need to write your custom data provider, which is inherited from the Devart.Data.Oracle.Linq.Provider.OracleDataProvider class.
JIC: We recommend you to use dotConnect for Oracle as a data provider when working with LinqConnect and Oracle. LinqConnect Professional Edition includes the Express editions of our data providers (dotConnect for Oracle bundled with LinqConnect provides basic connectivity features) and supports the corresponding databases. Please refer to: http://www.devart.com/linqconnect/editions.html

Is there any example of a custom provider inheriting from OracleDataProvider?

We are sending you a test project to the e-mail address you have provided in your forum profile, that demonstrates the way to implement a custom data provider. Please check that the letter is not blocked by your mail filter.

Please tell us about the results.