private static bool TryParseHtmlTagHtmlComment(ref StringSlice text, ref ValueStringBuilder builder)
{
var c = text.NextChar();
if (c != '-')
{
return(false);
}
builder.Append('-');
builder.Append('-');
if (text.PeekChar() == '>')
{
return(false);
}
var countHyphen = 0;
while (true)
{
c = text.NextChar();
if (c == '\0')
{
return(false);
}
if (countHyphen == 2)
{
if (c == '>')
{
builder.Append('>');
text.SkipChar();
return(true);
}
return(false);
}
countHyphen = c == '-' ? countHyphen + 1 : 0;
builder.Append(c);
}
}
private static bool TryParseHtmlTag(ref StringSlice text, ref ValueStringBuilder builder)
{
var c = text.CurrentChar;
if (c != '<')
{
return(false);
}
c = text.NextChar();
builder.Append('<');
switch (c)
{
case '/':
return(TryParseHtmlCloseTag(ref text, ref builder));
case '?':
return(TryParseHtmlTagProcessingInstruction(ref text, ref builder));
case '!':
builder.Append(c);
c = text.NextChar();
if (c == '-')
{
return(TryParseHtmlTagHtmlComment(ref text, ref builder));
}
if (c == '[')
{
return(TryParseHtmlTagCData(ref text, ref builder));
}
return(TryParseHtmlTagDeclaration(ref text, ref builder));
}
return(TryParseHtmlTagOpenTag(ref text, ref builder));
}
internal static bool TryParseHtmlTagOpenTag(ref StringSlice text, ref ValueStringBuilder builder)
{
var c = text.CurrentChar;
// Parse the tagname
if (!c.IsAlpha())
{
return(false);
}
builder.Append(c);
while (true)
{
c = text.NextChar();
if (c.IsAlphaNumeric() || c == '-')
{
builder.Append(c);
}
else
{
break;
}
}
bool hasAttribute = false;
while (true)
{
var hasWhitespaces = false;
// Skip any whitespaces
while (c.IsWhitespace())
{
builder.Append(c);
c = text.NextChar();
hasWhitespaces = true;
}
switch (c)
{
case '\0':
return(false);
case '>':
text.SkipChar();
builder.Append(c);
return(true);
case '/':
builder.Append('/');
c = text.NextChar();
if (c != '>')
{
return(false);
}
text.SkipChar();
builder.Append('>');
return(true);
case '=':
if (!hasAttribute)
{
return(false);
}
builder.Append('=');
// Skip any spaces after
c = text.NextChar();
while (c.IsWhitespace())
{
builder.Append(c);
c = text.NextChar();
}
// Parse a quoted string
if (c == '\'' || c == '\"')
{
builder.Append(c);
char openingStringChar = c;
while (true)
{
c = text.NextChar();
if (c == '\0')
{
return(false);
}
if (c != openingStringChar)
{
builder.Append(c);
}
else
{
break;
}
}
builder.Append(c);
c = text.NextChar();
}
else
{
// Parse until we match a space or a special html character
int matchCount = 0;
while (true)
{
if (c == '\0')
{
return(false);
}
if (c == ' ' || c == '\n' || c == '"' || c == '\'' || c == '=' || c == '<' || c == '>' || c == '`')
{
break;
}
matchCount++;
builder.Append(c);
c = text.NextChar();
}
// We need at least one char after '='
if (matchCount == 0)
{
return(false);
}
}
hasAttribute = false;
continue;
default:
if (!hasWhitespaces)
{
return(false);
}
// Parse the attribute name
if (!(c.IsAlpha() || c == '_' || c == ':'))
{
return(false);
}
builder.Append(c);
while (true)
{
c = text.NextChar();
if (c.IsAlphaNumeric() || c == '_' || c == ':' || c == '.' || c == '-')
{
builder.Append(c);
}
else
{
break;
}
}
hasAttribute = true;
break;
}
}
}
private static bool TryParseHtmlTagProcessingInstruction(ref StringSlice text, ref ValueStringBuilder builder)
{
builder.Append('?');
var prevChar = '\0';
while (true)
{
var c = text.NextChar();
if (c == '\0')
{
return(false);
}
if (c == '>' && prevChar == '?')
{
builder.Append('>');
text.SkipChar();
return(true);
}
prevChar = c;
builder.Append(c);
}
}