Manually iterating over a selection of XML elements (C#, XDocument)
- by user316117
What is the “best practice” way of manually iterating (i.e., one at a time with a “next” button) over a set of XElements in my XDocument? Say I select the set of elements I want thusly:
var elems = from XElement el in m_xDoc.Descendants()
where (el.Name.LocalName.ToString() == "q_a")
select el;
I can use an IEnumerator to iterate over them, i.e.,
IEnumerator m_iter;
But when I get to the end and I want to wrap around to the beginning if I call Reset() on it, it throws a NotSupportedException. That’s because, as the Microsoft C# 2.0 Specification under chapter 22 "Iterators" says "Note that enumerator objects do not support the IEnumerator.Reset method. Invoking this method causes a System.NotSupportedException to be thrown ."
So what IS the right way of doing this? And what if I also want to have bidirectional iteration, i.e., a “back” button, too?
Someone on a Microsoft discussion forum said I shouldn’t be using IEnumerable directly anyway. He said there was a way to do what I want with LINQ but I didn’t understand what. Someone else suggested dumping the XElements into a List with ToList(), which I think would work, but I wasn’t sure it was “best practice”. Thanks in advance for any suggestions!
