使用输入字符串在 c# 中生成 CRC32 校验和

Question

I'm trying to generate a CRC32 checksum for the Kraken exchange's orderbooks as described here . I found another post in SO that referenced this Github file in order to generate the CRC32 checksum. The issue I have is that I need to generate the checksum based off an input string , where all of the checksum functions I've found take a byte[] as an input.

I tried converting the string to a byte[] , but it doesn't give me the expected result that I should be getting as per the Kraken docs.

string inputString = "50055005010500501550050205005025500503050050355005040500504550050505005000500499550049905004980500497550049705004965500496050049555004950500";
        
Crc32 crc32 = new Crc32();
var byteArr = crc32.ComputeHash(Encoding.ASCII.GetBytes(inputString));
    
Console.WriteLine(Encoding.ASCII.GetString(byteArr));

The value this logs will be ":??" , where as I'm supposed to be getting "974947235" .

Clearly, I must be doing something completely wrong here. What am I missing?

Answer 1

ComputeHash returns byte[] , so you will get four bytes back. Your 974947235 becomes in hex 3a, 1c, 83, a3 . Or 58, 28, 131, 163 in decimal. Trying to print random bytes as characters can only lead to angst and frustration. Print them as numbers. Note that 58 is the colon (":") character, so in fact your first character is correct.

By the way, there are many CRC-32's, but you seem to have stumbled on to the correct one, as the string you provided does indeed result in the CRC-32/ISO-HDLC : 974947235 .

Answer 2

Mark's post got me half way there. The solution I found was to convert to a hex, and then convert that hex into an int , like so:

Crc32 crc32 = new Crc32();
byte[] byteArr = crc32.ComputeHash(Encoding.ASCII.GetBytes(s));

string hex = BitConverter.ToString(byteArr);

int desiredInt = int.Parse(
   hex.Replace("-", string.Empty),
   System.Globalization.NumberStyles.HexNumber);