如何在Python中逐字节修改十六进制字符串？

Question

I'm programming a little piece of code to swap headers between .bmp and .wav files. I managed to extract raw bytes (eg \\x00\\x12 ) and transform it into a string ( 0012 ) but what I wanna do now is split the string in a way that I can modify it two bytes by two bytes. This means that I have my hex string, for example FACB3D52 , and I want it to be split out FACB so that I can apply rules in it (if there is A, replace by B), and then it moves forward to 3D52 , apply the same rules, and reassemble the string so that it outputs FBCB3D52

I do not have much experience in Python and I really have no clues on how I should go for this problem

Answer 1

If you are applying the same rule to each chunk of the hexadecimal number, you can use the following.

hexstr = "FACB3D52"

hexlist = [hexstr[i:i+4] for i in range(len(hexstr)//4)] # Split into list of substrings
new_hexlist = [substr.replace('A', 'B') for substr in hexlist] # Apply rule to each substring
new_hexstr = ''.join(new_hexlist) # Join substrings back to form final string

print(new_hexstr)

Output

FBCBBCB3