DesignerTransaction CreateTransaction(object obj)
{
IComponent com = obj as IComponent;
if (com == null || com.Site == null) return null;
IDesignerHost dh = (IDesignerHost) com.Site.GetService (typeof(IDesignerHost));
if (dh == null) return null;
DesignerTransaction tran = dh.CreateTransaction ();
IComponentChangeService ccs = (IComponentChangeService) com.Site.GetService (typeof(IComponentChangeService));
if (ccs != null)
ccs.OnComponentChanging (com, parentRow.PropertyDescriptor);
return tran;
}