/// <summary>See <see cref="XmlReader.Read"/></summary>
public override bool Read()
{
_state = XIncludingReaderState.Default;
//Read internal reader
bool baseRead = _reader.Read();
if (baseRead)
{
//If we are including and including reader is at 0 depth -
//we are at a top level included item
_topLevel = (_readers.Count > 0 && _reader.Depth == 0) ? true : false;
if (_topLevel && _reader.NodeType == XmlNodeType.Attribute)
//Attempt to include an attribute or namespace node
throw new AttributeOrNamespaceInIncludeLocationError(Properties.Resources.AttributeOrNamespaceInIncludeLocationError);
if (_topLevel && ((XmlReader)_readers.Peek()).Depth == 0 &&
_reader.NodeType == XmlNodeType.Element)
{
if (_gotTopIncludedElem)
//Attempt to include more than one element at the top level
throw new MalformedXInclusionResultError(Properties.Resources.MalformedXInclusionResult);
else
_gotTopIncludedElem = true;
}
if (_topLevel)
{
//Check if included item has different language
_differentLang = AreDifferentLangs(_reader.XmlLang, ((XmlReader)_readers.Peek()).XmlLang);
if (_reader.NodeType == XmlNodeType.Element)
{
//Record real xml:base index
_realXmlBaseIndex = -1;
int i = 0;
while (_reader.MoveToNextAttribute())
{
if (_reader.Name == _keywords.XmlBase)
{
_realXmlBaseIndex = i;
break;
}
i++;
}
_reader.MoveToElement();
}
}
switch (_reader.NodeType)
{
case XmlNodeType.XmlDeclaration:
case XmlNodeType.Document:
case XmlNodeType.DocumentType:
case XmlNodeType.DocumentFragment:
//This stuff should not be included into resulting infoset,
//but should be inclused into acquired infoset
return _readers.Count > 0 ? Read() : baseRead;
case XmlNodeType.Element:
//Check for xi:include
if (IsIncludeElement(_reader))
{
//xi:include element found
//Save current reader to possible fallback processing
XmlReader current = _reader;
try
{
return ProcessIncludeElement();
}
catch (FatalException fe)
{
throw fe;
}
catch (Exception e)
{
//Let's be liberal - any exceptions other than fatal one
//should be treated as resource error
//Console.WriteLine("Resource error has been detected: " + e.Message);
//Start fallback processing
if (!current.Equals(_reader))
{
_reader.Close();
_reader = current;
}
_prevFallbackState = _fallbackState;
return ProcessFallback(_reader.Depth, e);
}
//No, it's not xi:include, check it for xi:fallback
}
else if (IsFallbackElement(_reader))
{
//Found xi:fallback not child of xi:include
IXmlLineInfo li = _reader as IXmlLineInfo;
if (li != null && li.HasLineInfo())
{
throw new XIncludeSyntaxError(String.Format(
CultureInfo.CurrentCulture,
Properties.Resources.FallbackNotChildOfIncludeLong,
_reader.BaseURI.ToString(), li.LineNumber,
li.LinePosition));
}
else
throw new XIncludeSyntaxError(String.Format(
CultureInfo.CurrentCulture,
Properties.Resources.FallbackNotChildOfInclude,
_reader.BaseURI.ToString()));
}
else
{
_gotElement = true;
goto default;
}
case XmlNodeType.EndElement:
//Looking for end of xi:fallback
if (_fallbackState.Fallbacking &&
_reader.Depth == _fallbackState.FallbackDepth &&
IsFallbackElement(_reader))
{
//End of fallback processing
_fallbackState.FallbackProcessed = true;
//Now read other ignored content till </xi:fallback>
return ProcessFallback(_reader.Depth - 1, null);
}
else
goto default;
default:
return baseRead;
}
}
else
{
//No more input - finish possible xi:include processing
if (_topLevel)
_topLevel = false;
if (_readers.Count > 0)
{
_reader.Close();
//Pop previous reader
_reader = (XmlReader)_readers.Pop();
//Successful include - skip xi:include content
if (!_reader.IsEmptyElement)
CheckAndSkipContent();
return Read();
}
else
{
if (!_gotElement)
throw new MalformedXInclusionResultError(Properties.Resources.MalformedXInclusionResult);
//That's all, folks
return false;
}
}
} // Read()
/// <summary>
/// Fallback processing.
/// </summary>
/// <param name="depth"><c>xi:include</c> depth level.</param>
/// <param name="e">Resource error, which caused this processing.</param>
/// <remarks>When inluding fails due to any resource error, <c>xi:inlcude</c>
/// element content is processed as follows: each child <c>xi:include</c> -
/// fatal error, more than one child <c>xi:fallback</c> - fatal error. No
/// <c>xi:fallback</c> - the resource error results in a fatal error.
/// Content of first <c>xi:fallback</c> element is included in a usual way.</remarks>
private bool ProcessFallback(int depth, Exception e)
{
//Read to the xi:include end tag
while (_reader.Read() && depth < _reader.Depth)
{
switch (_reader.NodeType)
{
case XmlNodeType.Element:
if (IsIncludeElement(_reader))
{
//xi:include child of xi:include - fatal error
IXmlLineInfo li = _reader as IXmlLineInfo;
if (li != null && li.HasLineInfo())
{
throw new XIncludeSyntaxError(String.Format(
CultureInfo.CurrentCulture,
Properties.Resources.IncludeChildOfIncludeLong,
BaseURI.ToString(),
li.LineNumber, li.LinePosition));
}
else
throw new XIncludeSyntaxError(String.Format(
CultureInfo.CurrentCulture,
Properties.Resources.IncludeChildOfInclude,
BaseURI.ToString()));
}
if (IsFallbackElement(_reader))
{
//Found xi:fallback
if (_fallbackState.FallbackProcessed)
{
IXmlLineInfo li = _reader as IXmlLineInfo;
if (li != null && li.HasLineInfo())
{
//Two xi:fallback
throw new XIncludeSyntaxError(String.Format(
CultureInfo.CurrentCulture,
Properties.Resources.TwoFallbacksLong,
BaseURI.ToString(),
li.LineNumber, li.LinePosition));
}
else
throw new XIncludeSyntaxError(String.Format(
CultureInfo.CurrentCulture, Properties.Resources.TwoFallbacks, BaseURI.ToString()));
}
if (_reader.IsEmptyElement)
{
//Empty xi:fallback - nothing to include
_fallbackState.FallbackProcessed = true;
break;
}
_fallbackState.Fallbacking = true;
_fallbackState.FallbackDepth = _reader.Depth;
return Read();
}
else
//Ignore anything else along with its content
SkipContent();
break;
default:
break;
}
}
//xi:include content is read
if (!_fallbackState.FallbackProcessed)
//No xi:fallback, fatal error
throw new FatalResourceException(e);
else
{
//End of xi:include content processing, reset and go forth
_fallbackState = _prevFallbackState;
return Read();
}
}
