BigInteger from Byte array

[graham]

Hi, congratulation on the library, it is simply amazing.

I am having a slight issue with the biginteger class when initialising from a byte array. For a given Byte array b, i have used

Set bigintvalue = BInt(b)
and then have check that the array has been set correctly with
Dim c() As Byte
c = urltobigint.ToArray
which results in an identical array as expected.

But the number produced when looking at the .ToString is not as expected.
The byte array: CDDA00AEEEB14D48882DFBC55DAA6504
Should result in a decimal value of: 273623673710640401018044282812286788868
which is correct when using java's bigint, but a different value is returned here.

I am not not sure where abouts i am going wrong, but any help would be appreciated.

[Kelly Ethridge]

Hello graham,

The problem comes from determining if the byte array contains a negative value or not. I check the highest bit for this and assume it's negative if set. If you were to resize the array with an extra 4 bytes, the parser will treat the byte array as positive. Padding the end(left most) with 4 bytes of zeros ensures a positive number. I know this is a kludge and may be difficult to support all scenarios. It's one of the things on the list to improve when I get a chance.

Kelly

[graham]

Thank you, that is brilliant, and now working perfectly . The extra 4 bytes are no problem, as i am working with fixed length byte arrays.
Thanks again for the help.