TreeIterator.cs

Go to the documentation of this file.

namespace System.Xml;
 
internal sealed class TreeIterator : BaseTreeIterator
{
    private readonly XmlNode _nodeTop;
 
    private XmlNode _currentNode;
 
    internal override XmlNode CurrentNode => _currentNode;
 
    internal TreeIterator(XmlNode nodeTop)
        : base(((XmlDataDocument)nodeTop.OwnerDocument).Mapper)
    {
        _nodeTop = nodeTop;
        _currentNode = nodeTop;
    }
 
    internal override bool Next()
    {
        XmlNode firstChild = _currentNode.FirstChild;
        if (firstChild != null)
        {
            _currentNode = firstChild;
            return true;
        }
        return NextRight();
    }
 
    internal override bool NextRight()
    {
        if (_currentNode == _nodeTop)
        {
            _currentNode = null;
            return false;
        }
        XmlNode nextSibling = _currentNode.NextSibling;
        if (nextSibling != null)
        {
            _currentNode = nextSibling;
            return true;
        }
        nextSibling = _currentNode;
        while (nextSibling != _nodeTop && nextSibling.NextSibling == null)
        {
            nextSibling = nextSibling.ParentNode;
        }
        if (nextSibling == _nodeTop)
        {
            _currentNode = null;
            return false;
        }
        _currentNode = nextSibling.NextSibling;
        return true;
    }
}