/// <summary>
/// When overridden in a derived class, compares the base Uniform Resource Identifiers (URIs) of two documents based upon the
/// order the documents were loaded by the XSLT processor (that is, the <see cref="T:System.Xml.Xsl.XslTransform"/> class).
/// </summary>
/// <param name="baseUri">The base URI of the first document to compare.</param>
/// <param name="nextbaseUri">The base URI of the second document to compare.</param>
/// <returns>
/// An integer value describing the relative order of the two base URIs: -1 if <paramref name="baseUri"/> occurs before <paramref name="nextbaseUri"/>; 0 if the two base URIs are identical; and 1 if <paramref name="baseUri"/> occurs after <paramref name="nextbaseUri"/>.
/// </returns>
public override int CompareDocument(string baseUri, string nextbaseUri)
{
return(_baseContext.CompareDocument(baseUri, nextbaseUri));
}
internal override XPathNavigator advance()
{
XPathNavigator res1, res2;
XmlNodeOrder order = 0;
if (advance1)
{
res1 = qy1.advance();
}
else
{
res1 = _last;
}
if (advance2)
{
res2 = qy2.advance();
}
else
{
res2 = _last;
}
if (res1 != null && res2 != null)
{
order = res1.ComparePosition(res2);
}
else if (res2 == null)
{
advance1 = true;
advance2 = false;
m_eNext = res1;
_last = null;
return(res1);
}
else
{
advance1 = false;
advance2 = true;
m_eNext = res2;
_last = null;
return(res2);
}
if (order == XmlNodeOrder.Same)
{
return(ProcessSamePosition(res1));
}
if (order == XmlNodeOrder.Before)
{
return(ProcessBeforePosition(res1, res2));
}
if (order == XmlNodeOrder.After)
{
return(ProcessAfterPosition(res1, res2));
}
//Now order is XmlNodeOrder.Unknown
XPathNavigator dummyres1 = res1.Clone();
dummyres1.MoveToRoot();
XPathNavigator dummyres2 = res2.Clone();
dummyres2.MoveToRoot();
int uriOrder = context.CompareDocument(dummyres1.BaseURI, dummyres2.BaseURI);
if (uriOrder == 0)
{
return(ProcessSamePosition(res1));
}
if (uriOrder < 0)
{
return(ProcessBeforePosition(res1, res2));
}
if (uriOrder > 0)
{
return(ProcessAfterPosition(res1, res2));
}
Debug.Assert(false, "should not be herein OrQuery.advance()");
return(null);
}