'ID' is not a member of 'System.Web.UI.WebControls.TreeNode'

Hi, people!
I've got a request to convert some projects from VS2003 to VS2012. But I've got some problems about Treeview and Treenodes. In my specifc case I need your help to replace the property Microsoft.Web.UI.WebControls.TreeNode.ID. In VS2012 this class seems to be replaced for System.Web.UI.WebControls.TreeNode. But when I replace the reference I get the follow error:
'ID' is not a member of 'System.Web.UI.WebControls.TreeNode'
I get the same error trying to use System.Web.UI.WebControls.Type. 
Is there someone that could already solve this problem???

Best Regards!