protected void btnUpdate_Click(object sender, EventArgs e)
    {
        if (RadTreeView1.SelectedNode == null)
        {
            ShowError("Selecione uma categoria!");
            return;
        }

        ProductManager manager = new ProductManager(this);
        ProductPart productPart = manager.GetProductPart(Convert.ToInt32(RadTreeView1.SelectedNode.Value));
        productPart.Name = txtProductPart.Text;
        productPart.Quantity = Convert.ToInt16(txtQuantity.Text);
        manager.DbContext.SubmitChanges();
        //DataManager.CurrentContext.SubmitChanges();

        BindTree();
    }
    protected void btnDelete_Click(object sender, EventArgs e)
    {
        if (RadTreeView1.SelectedNode == null)
        {
            ShowError("Selecione uma categoria!");
            return;
        }
        ProductManager manager = new ProductManager(this);
        ProductPart productPart = manager.GetProductPart(Convert.ToInt32(RadTreeView1.SelectedNode.Value));

        try
        {
            manager.DeleteProductPart(productPart);
        }
        catch (Exception ex)
        {
            ShowError(ex.Message.ToString());
            return;
        }

        BindTree();
    }
 protected void RadTreeView1_NodeBound(object o, RadTreeNodeEventArgs e)
 {
     ProductManager manager = new ProductManager(this);
     ProductPart productPart = manager.GetProductPart(Convert.ToInt32(e.Node.Value));
     e.Node.Text += " (" + productPart.Quantity + ")";
     e.Node.Expanded = true;
 }