System.Globalization.FormatProvider.Number.FormatExponent C# (CSharp) Method

            private static unsafe void FormatExponent(StringBuilder sb, NumberFormatInfo info, int value, char expChar, int minDigits, bool positiveSign)
            {
                sb.Append(expChar);

                if (value < 0)
                {
                    sb.Append(info.NegativeSign);
                    value = -value;
                }
                else
                {
                    if (positiveSign)
                        sb.Append(info.PositiveSign);
                }

                char* digits = stackalloc char[11];
                int index = 10;
                Int32ToDecChars(digits, ref index, (uint)value, minDigits);
                int i = 10 - index;
                while (--i >= 0)
                    sb.Append(digits[index++]);
            }