Question

I’m looking for a simple way to decode data stored in the Decimal64 format (described here: http://en.wikipedia.org/wiki/Decimal64_floating-point_format) using C#.

Any thoughts?

Answer 1

Looked everywhere for it, finally we implemented it ourselves.

Update
Some of you has asked us for the code – here is our code for it, We call it Float Decimal, I think it matches what Decimal 64 does – but no guarantees – please check for yourself.

Also note – that the value of _size should be 8.

 if (bytes[0] == 0) return 0;
        var s = "";
        for (var i = 1; i < bytes.Length; i++)
            s += bytes[i].ToString("X").PadLeft(2, '0');
        return decimal.Parse("." + s.TrimEnd('0')) * (decimal)Math.Pow(10 , ((bytes[0] & ~128) - 64)) * ((bytes[0] & 128) > 0 ? -1 : 1);

To save:

 if (value != 0)
        {
            var negative = value < 0;
            var s = value.ToDecimal().ToString(CultureInfo.InvariantCulture).TrimStart('-', '0');
            var i = s.IndexOf('.');
            if (i >= 0)
            {
                s = s.Remove(i, 1);
                if (i == 0)
                {
                    i = s.Length;
                    s = s.TrimStart('0');
                    i = s.Length-i;
                }
            }
            else i = s.Length;
            bytes[0] = (byte)(64 + i + (negative ? 128 : 0));
            s = s.PadRight((_size - 1) * 2, '0');
            for (var j = 1; j < _size && (j - 1) * 2 < s.Length; j++)
                bytes[j] = byte.Parse(s.Substring((j - 1) * 2, 2), System.Globalization.NumberStyles.HexNumber);
        }