converting GUID to long [closed]

Answer 1

No, a GUID is 128 bit so won't fit in your long since that is 64 bit. A System.Decimal is 128 bit so will get you a long way, but of course that also has it's limits. Even if you save your counter in a string it has its limits. Computers alsways have limits, you will have to find one which is big enough so you can continue for a while.

edit:

In .Net 4.0 there is a BigInteger which can be pretty big, but remember, even that has its limits since it has to fit in memory.

Answer 2

A GUID is a 128-bit integer. A long is a Signed 64-bit integer. While a ulong can have values from 0 to 18,446,744,073,709,551,615. Is that enough? Or do you wish to use decimal?

Answer 3

The problem is that the set of GUID far outnumbers the set of all integers long precision. So really you are shrinking the cardinality of choices significantly. There is no good reason to do this.

If you want to keep increasing a number and not worry about it, there's a library IntX that handles big numbers. You could store the local state of your number generator in a file or in memory and you'll have an ever increasing number. (well sort of)

Answer 4

you could try something like this.

byte[] gb = Guid.NewGuid().ToByteArray();
int i = BitConverter.ToInt32(gb,0);

long l = BitConverter.ToInt64(gb,0);

I am not sure If it is very secure. :p