internal char[] ConsumeCharacterReference()
{
var currentInputCharacter = bufferReader.Peek();
switch (currentInputCharacter)
{
case '\t':
case '\n':
case '\r':
case ' ':
case '<':
case '&':
case EofMarker:
return(Nothing);
case '#':
bufferReader.Consume();
var afterNumberSignCharacter = bufferReader.Peek();
int codepoint;
switch (afterNumberSignCharacter)
{
case 'x':
case 'X':
bufferReader.Consume();
codepoint = bufferReader.ConsumeHexDigits();
if (codepoint == int.MinValue)
{
bufferReader.Reconsume('#');
bufferReader.Reconsume(afterNumberSignCharacter);
ParseError(ParseErrorMessage.UnexpectedCharacterInStream);
return(Nothing);
}
break;
default:
codepoint = bufferReader.ConsumeDigits();
if (codepoint == int.MinValue)
{
bufferReader.Reconsume('#');
ParseError(ParseErrorMessage.UnexpectedCharacterInStream);
return(Nothing);
}
break;
}
if (bufferReader.Consume() != ';')
{
ParseError(ParseErrorMessage.UnexpectedCharacterInStream);
}
var replacementCharacter = HtmlChar.GetReplacementCharacterReference(codepoint);
if (replacementCharacter.HasValue)
{
ParseError(ParseErrorMessage.UnexpectedCharacterInStream);
return(new[] { replacementCharacter.Value });
}
if (HtmlChar.IsCharacterReferenceReplacementToken(codepoint))
{
return(new[] { HtmlChar.ReplacementCharacter });
}
if (HtmlChar.IsCharacterReferenceParseError(codepoint))
{
ParseError(ParseErrorMessage.UnexpectedCharacterInStream);
return(Nothing);
}
return(char.ConvertFromUtf32(codepoint).ToCharArray());
default:
if (currentInputCharacter == additionalAllowedCharacter)
{
return(Nothing);
}
var characterReferenceBuffer = bufferReader.Peek(35);
var startIndex = characterReferenceBuffer.IndexOf(';');
startIndex = startIndex == -1 ? characterReferenceBuffer.Length : startIndex + 1;
for (var i = startIndex; i > 0; i--)
{
var characterReferenceAttempt = characterReferenceBuffer.Substring(0, i);
var characterReferenceResult = HtmlChar.GetCharactersByCharacterReference(characterReferenceAttempt);
if (characterReferenceResult == null)
{
continue;
}
if ((additionalAllowedCharacter == '"' || additionalAllowedCharacter == '\'') &&
characterReferenceBuffer[i - 1] != ';' && characterReferenceBuffer.Length > i &&
(characterReferenceBuffer[i] == '=' ||
(characterReferenceBuffer[i] >= 'A' && characterReferenceBuffer[i] <= 'Z') ||
(characterReferenceBuffer[i] >= 'a' && characterReferenceBuffer[i] <= 'z') ||
(characterReferenceBuffer[i] >= '0' && characterReferenceBuffer[i] <= '9')))
{
if (characterReferenceBuffer[i] == '=')
{
ParseError(ParseErrorMessage.UnexpectedCharacterInStream);
}
return(Nothing);
}
bufferReader.Consume(characterReferenceAttempt.Length);
if (characterReferenceBuffer[i - 1] != ';')
{
ParseError(ParseErrorMessage.UnexpectedCharacterInStream);
}
return(characterReferenceResult);
}
for (var i = 0; i < characterReferenceBuffer.Length; i++)
{
if ((characterReferenceBuffer[i] >= 'A' && characterReferenceBuffer[i] <= 'Z') ||
(characterReferenceBuffer[i] >= 'a' && characterReferenceBuffer[i] <= 'z') ||
(characterReferenceBuffer[i] >= '0' && characterReferenceBuffer[i] <= '9'))
{
continue;
}
if (characterReferenceBuffer[i] != ';')
{
return(Nothing);
}
if (i > 0)
{
ParseError(ParseErrorMessage.UnexpectedCharacterInStream);
}
return(Nothing);
}
return(Nothing);
}
}