private object TraverseMember(object target, MemberTraversal member, bool isLastPathSegment)
{
if (target == null) return null;
object result = null;
// Is Target a Collection?
// Extract first item
target.TryAs<IEnumerable>(collection =>
{
var list = Enumerable.Cast<object>(collection);
var newTarget = list.FirstOrDefault();
result = TraverseMember(newTarget, member, isLastPathSegment);
});
if (result == null)
{
// Target is a single object
if (string.IsNullOrEmpty(member.MemberName))
// Self
result = target;
else
// Get Related Member
result = ReflectionHelper.GetMemberValue(target, member.MemberName);
// Is it a Collection?
result.TryAs<IEnumerable>(collection =>
{
// If not last path segment
// or supposed to extract item
bool shouldExtractItem = !isLastPathSegment || member is ExtractFromCollectionTraversal;
if (shouldExtractItem)
result = ExtractItemFromCollection(collection.Cast<object>().ToList(), member);
});
}
return result;
}
private object ExtractItemFromCollection(List<object> collection, MemberTraversal member)
{
object result = null;
if (collection == null || collection.Count == 0)
return null;
// By default, Extract first item
result = collection.First();
// or, Extract specific item from collection
member.TryAs<ExtractFromCollectionTraversal>(extractTraversal =>
{
result = collection[extractTraversal.IndexToExtract];
});
return result;
}
