private static bool ParseFraction(ref __DTString str, out double result) {
result = 0;
double decimalBase = 0.1;
int digits = 0;
char ch;
while (str.GetNext()
&& IsDigit(ch = str.m_current)) {
result += (ch - '0') * decimalBase;
decimalBase *= 0.1;
digits++;
}
return (digits > 0);
}