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<h1>Id</h1>
<p MadCap:conditions="Primary..NET,Primary.c#,Primary.All languages">
<pre class="prettyprint" xml:space="preserve">Id.cs
/**//* Copyright (C) 2004 - 2008 Versant Inc. http://www.db4o.com */
using Db4objects.Db4o;
using Db4objects.Db4o.<span class="MCPopup"><a href="javascript:void(0);" class="MCPopupSpot" onclick="FMCPopup( event, this ); return false;" MadCap:src="../../../../activation.htm">Activation<img style="border: none;margin-left: 5px;" src="../../../../../SkinSupport/ExpandingClosed.gif" MadCap:altsrc="../../../../../SkinSupport/ExpandingOpen.gif" class="MCExpandingIcon" onload="if ( typeof( FMCPreloadImage ) == 'function' ) { FMCPreloadImage( '../../../../../SkinSupport/ExpandingOpen.gif' ); }" /></a></span>;
using Db4objects.Db4o.<span class="MCTextPopup"><a href="javascript:void(0);" class="MCTextPopupSpot" onclick="FMCTextPopup( event, this ); return false;">TA<img style="border: none;margin-left: 5px;" src="../../../../../SkinSupport/ExpandingClosed.gif" MadCap:altsrc="../../../../../SkinSupport/ExpandingOpen.gif" class="MCExpandingIcon" onload="if ( typeof( FMCPreloadImage ) == 'function' ) { FMCPreloadImage( '../../../../../SkinSupport/ExpandingOpen.gif' ); }" /></a><span class="MCTextPopupBody" style="display: none; ">Transparent Activation</span></span>;
namespace Db4objects.Db4odoc.<span class="MCTextPopup"><a href="javascript:void(0);" class="MCTextPopupSpot" onclick="FMCTextPopup( event, this ); return false;">TP<img style="border: none;margin-left: 5px;" src="../../../../../SkinSupport/ExpandingClosed.gif" MadCap:altsrc="../../../../../SkinSupport/ExpandingOpen.gif" class="MCExpandingIcon" onload="if ( typeof( FMCPreloadImage ) == 'function' ) { FMCPreloadImage( '../../../../../SkinSupport/ExpandingOpen.gif' ); }" /></a><span class="MCTextPopupBody" style="display: none; ">Transparent Persistence</span></span>.Rollback
{
public class Id : IActivatable
{
int _number = 0;
[System.NonSerialized]
IActivator _activator;
public Id(int number)
{
_number = number;
}
// Bind the class to an object container
public void Bind(IActivator activator)
{
if (_activator == activator)
{
return;
}
if (activator != null && null != _activator)
{
throw new System.InvalidOperationException();
}
_activator = activator;
}
// activate the object fields
public void Activate(ActivationPurpose purpose)
{
if (_activator == null)
return;
_activator.Activate(purpose);
}
public void Change(int number)
{
Activate(ActivationPurpose.Write);
_number = number;
}
public override string ToString()
{
Activate(ActivationPurpose.Read);
return _number.ToString();
}
}
}</pre>
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<p MadCap:conditions="Primary..NET,Primary.VB.NET,Primary.All languages">
<pre class="prettyprint lang-vb" xml:space="preserve">Id.vb
' Copyright (C) 2004 - 2008 Versant Inc. http://www.db4o.com
Imports Db4objects.Db4o
Imports Db4objects.Db4o.Activation
Imports Db4objects.Db4o.TA
Namespace Db4objects.Db4odoc.TP.Rollback
Public Class Id
Implements IActivatable
Private _number As Integer = 0
<Transient()> _
Private _activator As IActivator
Public Sub New(ByVal number As Integer)
_number = number
End Sub
' Bind the class to an object container
Public Sub Bind(ByVal activator As IActivator) _
Implements IActivatable.Bind
If _activator Is activator Then
Return
End If
If activator IsNot Nothing AndAlso _activator _
IsNot Nothing Then
Throw New System.InvalidOperationException()
End If
_activator = activator
End Sub
' activate the object fields
Public Sub Activate(ByVal purpose As ActivationPurpose) _
Implements IActivatable.Activate
If _activator Is Nothing Then
Return
End If
_activator.Activate(purpose)
End Sub
Public Sub Change(ByVal number As Integer)
Activate(ActivationPurpose.Write)
_number = number
End Sub
Public Overloads Overrides Function ToString() As String
Activate(ActivationPurpose.Read)
Return _number.ToString()
End Function
End Class
End Namespace</pre>
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<p MadCap:conditions="Global.Primary:vb" />
<p MadCap:conditions="Primary.Online">Download example code:</p>
<p MadCap:conditions="Primary.Online">
<MadCap:conditionalText MadCap:conditions="Primary..NET,Primary.VB.NET,Primary.All languages"><a href="../rollbackvb.zip">VB.NET </a>
</MadCap:conditionalText>
<MadCap:conditionalText MadCap:conditions="Primary..NET,Primary.c#,Primary.All languages"><a href="../rollbackcs.zip">c# </a>
</MadCap:conditionalText>
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