PrecedingSiblingDocOrderIterator.cs

Go to the documentation of this file.

using System.ComponentModel;
using System.Xml.XPath;
 
namespace System.Xml.Xsl.Runtime;
 
[EditorBrowsable(EditorBrowsableState.Never)]
public struct PrecedingSiblingDocOrderIterator
{
    private XmlNavigatorFilter _filter;
 
    private XPathNavigator _navCurrent;
 
    private XPathNavigator _navEnd;
 
    private bool _needFirst;
 
    private bool _useCompPos;
 
    public XPathNavigator Current => _navCurrent;
 
    public void Create(XPathNavigator context, XmlNavigatorFilter filter)
    {
        _filter = filter;
        _navCurrent = XmlQueryRuntime.SyncToNavigator(_navCurrent, context);
        _navEnd = XmlQueryRuntime.SyncToNavigator(_navEnd, context);
        _needFirst = true;
        _useCompPos = _filter.IsFiltered(context);
    }
 
    public bool MoveNext()
    {
        if (_needFirst)
        {
            if (!_navCurrent.MoveToParent())
            {
                return false;
            }
            if (!_filter.MoveToContent(_navCurrent))
            {
                return false;
            }
            _needFirst = false;
        }
        else if (!_filter.MoveToFollowingSibling(_navCurrent))
        {
            return false;
        }
        if (_useCompPos)
        {
            return _navCurrent.ComparePosition(_navEnd) == XmlNodeOrder.Before;
        }
        if (_navCurrent.IsSamePosition(_navEnd))
        {
            _useCompPos = true;
            return false;
        }
        return true;
    }
}