Question

I need to validate the ConnectionString property on a DataContext object to ensure that LINQ can get a connection to the database. I have tried the two methods below but, they lock up the application if the connection string is invalid. Is there another way in LINQ to do this?

    public static bool TestDBConnection(connectionString)
    {
        bool result = true;
        DomainClassesDataContext db = new DomainClassesDataContext(connectionString);

        try
        {
            // Hangs if connectionString is invalid rather than throw an exception
            db.Connection.Open();

            // Initially, I was just trying to call DatabaseExists but, this hangs as well if the conn string is invalid
            if (!db.DatabaseExists())
            {
                result = false;
            }
        }
        catch (Exception ex)
        {
            result = false;
            logger.Fatal(ex.Message);
            logger.Fatal(ex.StackTrace);
        }
        finally
        {
            db.Dispose();
        }

        return result;
    }

Answer 1

Set the Connection Timeout in the connection string to a low value like 5s.

Opening is not enough. You might get a stale, pooled connection. Execute a query: SELECT NULL.