How to separate the character in binary form and checksum them c#

Question

ff03c1 3d

how to xor this string and get checksum 3d ?

the scenario is:

i get string like ff03c13d. (there are other models with longer lengths). and i should check crc in hex;

like this:

ff xor 03 xor c1 and if result equal the last two characters or the last byte (like 3d) return True.

thanks for your help

Answer 1

Linq, Where, Select, Aggregate, ToString

var hex = "ff03c1";
var result = Enumerable.Range(0, hex.Length)
                       .Where(x => x % 2 == 0)
                       .Select(x => Convert.ToInt32(hex.Substring(x, 2), 16))
                       .Aggregate((i, i1) => i ^ i1)
                       .ToString("X");

Console.WriteLine(result);

Full Demo Here

Method

public static bool Check(string hex)
{
   return Enumerable.Range(0, hex.Length-2)
                    .Where(x => x % 2 == 0)
                    .Select(x => Convert.ToInt32(hex.Substring(x, 2), 16))
                    .Aggregate((i, i1) => i ^ i1)
                    .ToString("x") == hex.Substring(hex.Length-2);
}

Usage

var hex = "ff03c13d";

Console.WriteLine(Check(hex));

Output

True