Global Activation Settings

c#:

configuration.ActivationDepth(activationDepth)

VB:

configuration.ActivationDepth(activationDepth)

configures global activation depth, which will be used for all objects instead of the default value. This method should be called before opening a database file.

c#:

configuration.ActivationDepth(activationDepth)

VB:

configuration.ActivationDepth(activationDepth)

has a similar effect, but the setting will be applied to the specific ObjectContainer and can be changed for the open database file.

ActivationExample.cs: TestActivationConfig
01private static void TestActivationConfig() 02 { 03 StoreSensorPanel(); 04 IConfiguration configuration = Db4oFactory.NewConfiguration(); 05 configuration.ActivationDepth(1); 06 IObjectContainer db = Db4oFactory.OpenFile(configuration, Db4oFileName); 07 try 08 { 09 Console.WriteLine("Object container activation depth = 1"); 10 IObjectSet result = db.Get(new SensorPanel(1)); 11 ListResult(result); 12 if (result.Count >0) 13 { 14 SensorPanel sensor = (SensorPanel)result[0]; 15 SensorPanel next = sensor.Next; 16 while (next != null) 17 { 18 Console.WriteLine(next); 19 next = next.Next; 20 } 21 } 22 } 23 finally 24 { 25 db.Close(); 26 } 27 }
ActivationExample.vb: TestActivationConfig
01Private Shared Sub TestActivationConfig() 02 StoreSensorPanel() 03 Dim configuration As IConfiguration = Db4oFactory.NewConfiguration() 04 configuration.ActivationDepth(1) 05 Dim db As IObjectContainer = Db4oFactory.OpenFile(configuration, Db4oFileName) 06 Try 07 Console.WriteLine("Object container activation depth = 1") 08 Dim result As IObjectSet = db.Get(New SensorPanel(1)) 09 ListResult(result) 10 If result.Count > 0 Then 11 Dim sensor As SensorPanel = CType(result(0), SensorPanel) 12 Dim nextSensor As SensorPanel = sensor.NextSensor 13 While Not nextSensor Is Nothing 14 Console.WriteLine(nextSensor) 15 nextSensor = nextSensor.NextSensor 16 End While 17 End If 18 Finally 19 db.Close() 20 End Try 21 End Sub

By configuring db4o you can have full control over activation behavior. The two extremes: