Casting oledb to Sqlclient objects

[waleednosir]

Dear Experts,

I have a situation , I am sure about the best approach for it. I have a database application that is designed to handle both SQLServer database and Oleddb "Access mdb" database. the issue is that during application start up , the application detects the configuration file and decides which database to use , eg , oledb to Sqlclient objects. the problem is that the application itself is, eg code to use teh sqlclient objects at different locations of the program. If i need to use oledb , i need to replace all of the sqlclient objects with oledb. who can i do it at run time. the bad solution will be to make at make both objects and decide which one to use , but the application is large. so it will be un-logic to use this approach. I tried to define an object as below

    Public aa As SqlClient.SqlConnection
    Public bb As OleDb.OleDbConnection
    Public gg as object
 
   if applicType="AccessDatabase" then directcast(gg,oledib.oleDbConnection") 

but this gave me an error .

I tried also :

   if applicType="AccessDatabase" then directcast(aa,oledib.oleDbConnection")
 

but gave an error that I can not cast sqlclient to oledb .


Any solution ?

Thanks,

[ZiadElmalki]

That is not possible because neither the OleDbConnection or SqlConnection derive from each other. In the System.Data namespace there are some basic classes and interface for ADO.NET. For connection could use IDbConnection interface as abstraction

[Frinavale]

Both the OleDBConnection class and the SqlConnection class inherit from the Common.DBConnection class.

So, in theory, you can declare your connection as a DbConnection and instantiate it as either a OleDbConnection or a SqlConnection later.

That way, when you're doing your direct cast, it will work properly.

-Frinny