Check if XML Element exists

Question

How can someone validate that a specific element exists in an XML file? Say I have an ever changing XML file and I need to verify every element exists before reading/parsing

Answer 1

//I am finding childnode ERNO at 2nd but last place

If StrComp(xmlnode(i).ChildNodes.Item(xmlnode(i).ChildNodes.Count - 1).Name.ToString(), "ERNO", CompareMethod.Text) = 0 Then
                xmlnode(i).ChildNodes.Item(xmlnode(i).ChildNodes.Count - 1).InnerText = c
            Else
                elem = xmldoc.CreateElement("ERNo")
                elem.InnerText = c.ToString
                root.ChildNodes(i).AppendChild(elem)
            End If