protected void FillCategories(DataSet dsContent, ref Telerik.Web.UI.RadTreeView treeView)
    {
        treeView.DataBind();
        if (treeView.Nodes.Count > 0)
        {
            if (dsContent.Tables.Count > 0)
                for (int i = 0; i < dsContent.Tables[0].Rows.Count; i++)
                {
                    Telerik.Web.UI.RadTreeNode node =
                        (Telerik.Web.UI.RadTreeNode)treeView.FindNodeByValue(dsContent.Tables[0].Rows[i]["CategoryID"].ToString());

                    if (node != null)
                        node.Checked = true;
                }
        }
    }