private static string ReadNumber(CharBuffer charBuffer)
{
char c = charBuffer.Head();
StringBuilder sb = new StringBuilder();
if (c == '-')
{
sb.Append(c);
charBuffer.Next();
c = charBuffer.Head();
}
if (!IsDigit(c))
{
ThrowHelper.Throw("invalid char for number: " + c);
}
while (IsDigit(c) || IsDecimal(c) || IsExp(c))
{
sb.Append(c);
charBuffer.Next();
c = charBuffer.Head();
}
return(sb.ToString());
}
private static string ReadString(CharBuffer charBuffer)
{
charBuffer.Next();
StringBuilder sb = new StringBuilder();
while (charBuffer.HasMore())
{
char c = charBuffer.Next();
if (c == '\\')
{
sb.Append(c);
c = charBuffer.Head();
if (!IsEscape(c))
{
ThrowHelper.Throw("invalid escape char \\" + c);
}
sb.Append(c);
}
else if (c == '"')
{
return(sb.ToString());
}
else if (c == '\r' || c == '\n')
{
ThrowHelper.Throw("Invalid character");
}
else
{
sb.Append(c);
}
}
ThrowHelper.Throw("unfinished string");
return(null);
}
private static char ReadNull(CharBuffer charBuffer)
{
char c = charBuffer.Head();
charBuffer.Get(4);
return(c);
}
private static char ReadBoolean(CharBuffer charBuffer)
{
char c = charBuffer.Head();
switch (c)
{
case 'f':
charBuffer.Get(5);
break;
case 't':
charBuffer.Get(4);
break;
default:
ThrowHelper.Throw("invalid boolean start: " + c);
break;
}
return(c);
}
private static JsonToken Read(CharBuffer charBuffer)
{
char c = charBuffer.Head();
while (IsWhiteSpace(c) && charBuffer.HasMore())
{
charBuffer.Next();
if (charBuffer.HasMore())
{
c = charBuffer.Head();
}
else
{
return(null);
}
}
switch (c)
{
case '{':
return(new JsonToken(JsonToken.TokenType.BeginObject, charBuffer.Next()));
case '}':
return(new JsonToken(JsonToken.TokenType.EndObject, charBuffer.Next()));
case '[':
return(new JsonToken(JsonToken.TokenType.BeginArray, charBuffer.Next()));
case ']':
return(new JsonToken(JsonToken.TokenType.EndArray, charBuffer.Next()));
case ',':
return(new JsonToken(JsonToken.TokenType.SepComma, charBuffer.Next()));
case ':':
return(new JsonToken(JsonToken.TokenType.SepColon, charBuffer.Next()));
case 'n':
return(new JsonToken(JsonToken.TokenType.Null, ReadNull(charBuffer)));
case 't':
case 'f':
return(new JsonToken(JsonToken.TokenType.Boolean, ReadBoolean(charBuffer)));
case '"':
return(new JsonToken(JsonToken.TokenType.String, ReadString(charBuffer)));
case '-':
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
case '.':
return(new JsonToken(JsonToken.TokenType.Number, ReadNumber(charBuffer)));
default:
ThrowHelper.Throw("unknown char :" + c);
break;
}
return(null);
}