/*
If the character reference is being consumed as part of an attribute, and the last character matched is not a U+003B SEMICOLON character (;), and the next character is either a U+003D EQUALS SIGN character (=) or in the range U+0030 DIGIT ZERO (0) to U+0039 DIGIT NINE (9), U+0041 LATIN CAPITAL LETTER A to U+005A LATIN CAPITAL LETTER Z, or U+0061 LATIN SMALL LETTER A to U+007A LATIN SMALL LETTER Z, then, for historical reasons, all the characters that were matched after the U+0026 AMPERSAND character (&) must be unconsumed, and nothing is returned.
*/
// 名前による文字参照を展開します。
protected ReferencedCharacterToken ConsumeNamedCharacterReference(Tokenizer t)
{
StringBuilder referenceName = new StringBuilder();
bool semicolonFound = false;
char? lastChar = t.CurrentInputChar;
while(lastChar.IsNameToken()){
referenceName.Append(lastChar);
lastChar = t.ConsumeChar();
}
if(lastChar == Chars.SEMICOLON){
referenceName.Append(lastChar);
semicolonFound = true;
} else {
// CurrentInputCharをreferenceNameの末尾にそろえる
t.UnConsume(1);
}
string originalString = referenceName.ToString();
string matchResult = null;
while(referenceName.Length > 0){
if(Chars.ExistsNamedChar(referenceName.ToString())){
matchResult = Chars.GetNamedChar(referenceName.ToString());
break;
}
referenceName.Remove(referenceName.Length-1, 1);
// CurrentInputCharをreferenceNameの末尾にそろえる
t.UnConsume(1);
}
if(matchResult == null){
if(semicolonFound){
// 名前がなく、セミコロンがある場合はパースエラー
// if the characters after the U+0026 AMPERSAND character (&) consist of a sequence of one or more characters in the range ASCII digits, lowercase ASCII letters, and uppercase ASCII letters, followed by a ";" (U+003B) character, then this is a parse error.
OnMessageRaised(new UnknownNamedCharacterReferenceWithSemicolonError(originalString));
} else {
// 名前がなくセミコロンがない場合はパースエラーにならない
OnMessageRaised(new UnknownNamedCharacterReferenceWithoutSemicolonWarning(originalString));
}
t.UnConsume(referenceName.Length);
return null;
}
if(!semicolonFound){
// 属性値の中のセミコロンなし文字参照は無視する
if(t.CurrentTokenState is CharacterReferenceInAttributeState && t.NextInputChar.IsSuffixOfIgnoreCharacterReferenceInAttribute()){
OnMessageRaised(new IgnoredCharacterReferenceInAttributeWarning(referenceName));
t.UnConsume(referenceName.Length);
return null;
}
// それ以外のセミコロンなし文字参照はエラー
OnMessageRaised(new NamedCharacterReferenceWithoutSemicolonError(referenceName));
}
ReferencedCharacterToken resultToken = new ReferencedCharacterToken(matchResult);
resultToken.OriginalString = referenceName.ToString();
return resultToken;
}
// 数値文字参照を展開します。
protected ReferencedCharacterToken ConsumeNumericCharacterReference(Tokenizer t)
{
char? c = t.ConsumeChar();
Predicate<char?> isNumeric = null;
System.Globalization.NumberStyles parseStyle = Chars.DecimalParseStyle;
string prefix = "";
string suffix = "";
if(c == 'x' || c == 'X'){
prefix = c.ToString();
isNumeric = Chars.IsHexDigit;
parseStyle = Chars.HexParseStyle;
c = t.ConsumeChar();
} else {
isNumeric = Chars.IsDigit;
}
StringBuilder matchResult = new StringBuilder();
while(isNumeric(c)){
matchResult.Append(c);
c = t.ConsumeChar();
}
if(matchResult.Length == 0){
OnMessageRaised(new EmptyNumericCharacterReferenceError());
return null;
}
string numberString = matchResult.ToString();
int resultNumber = int.Parse(numberString, parseStyle);
string result = GetNumberedChar(t, resultNumber);
if(c == Chars.SEMICOLON){
suffix += Chars.SEMICOLON;
} else {
OnMessageRaised(new NumericCharacterReferenceWithoutSemicolonError());
t.UnConsume(1);
}
string originalString = prefix + numberString + suffix;
ReferencedCharacterToken resultToken = new ReferencedCharacterToken(result);
resultToken.OriginalString = originalString;
return resultToken;
}