private void Form1_Load(object sender, System.EventArgs e)
        {
            Item item1 = ItemCache.GetItem(@"c:\sample.xml");
            System.Diagnostics.Trace.WriteLine(item1.Code);
            item1.Code = "cod0123456789";
            item1.Update();
            item1 = null;

            System.GC.Collect();

            Item item2 = ItemCache.GetItem(@"c:\sample.xml");
            System.Diagnostics.Trace.WriteLine(item2.Code);
        }