/// <summary>
/// Return a following sibling of the specified node that has the specified type. If no such
/// sibling exists, then do not set pageNode or idxNode and return false.
/// </summary>
public static bool GetContentSibling(ref XPathNode[] pageNode, ref int idxNode, XPathNodeType typ)
{
XPathNode[] page = pageNode;
int idx = idxNode;
int mask = XPathNavigatorEx.GetContentKindMask(typ);
Debug.Assert(pageNode != null && idxNode != 0, "Cannot pass null argument(s)");
if (page[idx].NodeType != XPathNodeType.Attribute)
{
while (true)
{
idx = page[idx].GetSibling(out page);
if (idx == 0)
{
break;
}
if (((1 << (int)page[idx].NodeType) & mask) != 0)
{
Debug.Assert(typ != XPathNodeType.Attribute && typ != XPathNodeType.Namespace);
pageNode = page;
idxNode = idx;
return(true);
}
}
}
return(false);
}
/// <summary>
/// Return the first child of the specified node that has the specified type (must be a content type). If no such
/// child exists, then do not set pageNode or idxNode and return false.
/// </summary>
public static bool GetContentChild(ref XPathNode[] pageNode, ref int idxNode, XPathNodeType typ)
{
XPathNode[] page = pageNode;
int idx = idxNode;
int mask;
Debug.Assert(pageNode != null && idxNode != 0, "Cannot pass null argument(s)");
// Only check children if at least one content-typed child exists
if (page[idx].HasContentChild)
{
mask = XPathNavigatorEx.GetContentKindMask(typ);
GetChild(ref page, ref idx);
do
{
if (((1 << (int)page[idx].NodeType) & mask) != 0)
{
// Never return attributes, as Attribute is not a content type
if (typ == XPathNodeType.Attribute)
{
return(false);
}
pageNode = page;
idxNode = idx;
return(true);
}
idx = page[idx].GetSibling(out page);
}while (idx != 0);
}
return(false);
}
/// <summary>
/// Get the next node that:
/// 1. Follows the current node in document order (includes descendants, unlike XPath following axis)
/// 2. Precedes the ending node in document order (if pageEnd is null, then all following nodes in the document are considered)
/// 3. Has the specified XPathNodeType (but Attributes and Namespaces never match)
/// If no such node exists, then do not set pageCurrent or idxCurrent and return false.
/// </summary>
public static bool GetContentFollowing(ref XPathNode[] pageCurrent, ref int idxCurrent, XPathNode[] pageEnd, int idxEnd, XPathNodeType typ)
{
XPathNode[] page = pageCurrent;
int idx = idxCurrent;
int mask = XPathNavigatorEx.GetContentKindMask(typ);
Debug.Assert(pageCurrent != null && idxCurrent != 0, "Cannot pass null argument(s)");
Debug.Assert(typ != XPathNodeType.Text, "Text should be handled by GetTextFollowing in order to take into account collapsed text.");
Debug.Assert(page[idx].NodeType != XPathNodeType.Attribute, "Current node should never be an attribute or namespace--caller should handle this case.");
// Since nodes are laid out in document order on pages, scan them sequentially
// rather than following sibling/child/parent links.
idx++;
do
{
if ((object)page == (object)pageEnd && idx <= idxEnd)
{
// Only scan to termination point
while (idx != idxEnd)
{
if (((1 << (int)page[idx].NodeType) & mask) != 0)
{
goto FoundNode;
}
idx++;
}
break;
}
else
{
// Scan all nodes in the page
while (idx < page[0].PageInfo.NodeCount)
{
if (((1 << (int)page[idx].NodeType) & mask) != 0)
{
goto FoundNode;
}
idx++;
}
}
page = page[0].PageInfo.NextPage;
idx = 1;
}while (page != null);
return(false);
FoundNode:
Debug.Assert(!page[idx].IsAttrNmsp, "GetContentFollowing should never return attributes or namespaces.");
// Found match
pageCurrent = page;
idxCurrent = idx;
return(true);
}