public UnionIteratorN(UnionIterator <TSource> previous, IEnumerable <TSource> next, int nextIndex)
: base(previous._comparer)
{
Debug.Assert(next != null);
Debug.Assert(nextIndex > 1);
_previous = previous;
_next = next;
_nextIndex = nextIndex;
}
// Invoked from XsltKey (XPathFunction)
public BaseIterator Evaluate(BaseIterator iter,
Expression valueExpr)
{
XPathNodeIterator i = iter;
if (iter.CurrentPosition == 0)
{
i = iter.Clone();
i.MoveNext();
}
XPathNavigator nav = i.Current;
object o = valueExpr.Evaluate(iter);
XPathNodeIterator it = o as XPathNodeIterator;
XsltContext ctx = iter.NamespaceManager as XsltContext;
BaseIterator result = null;
if (it != null)
{
while (it.MoveNext())
{
ArrayList nodes = GetNodesByValue(
nav, it.Current.Value, ctx);
if (nodes == null)
{
continue;
}
ListIterator tmp =
new ListIterator(nodes, ctx);
if (result == null)
{
result = tmp;
}
else
{
result = new UnionIterator(
iter, result, tmp);
}
}
}
else
{
ArrayList nodes = GetNodesByValue(
nav, XPathFunctions.ToString(o), ctx);
if (nodes != null)
{
result = new ListIterator(nodes, ctx);
}
}
return(result != null ? result : new NullIterator(iter));
}
public static IEnumerable <TSource> Union <TSource>(this IEnumerable <TSource> first, IEnumerable <TSource> second, IEqualityComparer <TSource> comparer)
{
if (first == null)
{
throw Error.ArgumentNull("first");
}
if (second == null)
{
throw Error.ArgumentNull("second");
}
UnionIterator <TSource> union = first as UnionIterator <TSource>;
return(union != null && EquivalentEqualityComparers(comparer, union._comparer) ? union.Union(second) : new UnionIterator2 <TSource>(first, second, comparer));
}
public BaseIterator Evaluate(BaseIterator iter, Expression valueExpr)
{
XPathNodeIterator xpathNodeIterator = iter;
if (iter.CurrentPosition == 0)
{
xpathNodeIterator = iter.Clone();
xpathNodeIterator.MoveNext();
}
XPathNavigator xpathNavigator = xpathNodeIterator.Current;
object obj = valueExpr.Evaluate(iter);
XPathNodeIterator xpathNodeIterator2 = obj as XPathNodeIterator;
XsltContext nsm = iter.NamespaceManager as XsltContext;
BaseIterator baseIterator = null;
if (xpathNodeIterator2 != null)
{
while (xpathNodeIterator2.MoveNext())
{
XPathNavigator xpathNavigator2 = xpathNodeIterator2.Current;
ArrayList nodesByValue = this.GetNodesByValue(xpathNavigator, xpathNavigator2.Value, nsm);
if (nodesByValue != null)
{
ListIterator listIterator = new ListIterator(nodesByValue, nsm);
if (baseIterator == null)
{
baseIterator = listIterator;
}
else
{
baseIterator = new UnionIterator(iter, baseIterator, listIterator);
}
}
}
}
else if (xpathNavigator != null)
{
ArrayList nodesByValue2 = this.GetNodesByValue(xpathNavigator, XPathFunctions.ToString(obj), nsm);
if (nodesByValue2 != null)
{
baseIterator = new ListIterator(nodesByValue2, nsm);
}
}
return((baseIterator == null) ? new NullIterator(iter) : baseIterator);
}
internal override IEnumerable <TSource> GetEnumerable(int index)
{
if (index > _nextIndex)
{
return(null);
}
UnionIteratorN <TSource> union = this;
while (index < union._nextIndex)
{
UnionIterator <TSource> previous = union._previous;
union = previous as UnionIteratorN <TSource>;
if (union == null)
{
Debug.Assert(index == 0 || index == 1);
Debug.Assert(EquivalentEqualityComparers(_comparer, previous._comparer));
return(previous.GetEnumerable(index));
}
}
return(union._next);
}
