Is it OK to open a DB4o file for query, insert, update multiple times?
- by Khnle
This is the way I am thinking of using DB4o. When I need to query, I would open the file, read and close:
using (IObjectContainer db = Db4oFactory.OpenFile(Db4oFactory.NewConfiguration(), YapFileName))
{
try
{
List<Pilot> pilots = db.Query<Pilot>().ToList<Pilot>();
}
finally
{
try { db.Close(); }
catch (Exception) { };
}
}
At some later time, when I need to insert, then
using (IObjectContainer db = Db4oFactory.OpenFile(Db4oFactory.NewConfiguration(), YapFileName))
{
try
{
Pilot pilot1 = new Pilot("Michael Schumacher", 100);
db.Store(pilot1);
}
finally
{
try { db.Close(); }
catch (Exception) { };
}
}
In this way, I thought I will keep the file more tidy by only having it open when needed, and have it closed most of the time. But I keep getting InvalidCastException
Unable to cast object of type 'Db4objects.Db4o.Reflect.Generic.GenericObject' to type 'Pilot'
What's the correct way to use DB4o?
