How to use the struct module and the h format specifier In Python

Using the bytes.hex() method to directly convert the bytearray to a hexadecimal string:

Import the struct module
Define the original bytearray
Convert each byte in the bytearray to a binary string using the struct.pack() function and the B format specifier
Convert each binary string to a hexadecimal string using the hex() method
Concatenate the hexadecimal strings for each byte into a single string using the join() method
Print the original bytearray and the resulting hexadecimal string

Python3

import struct
 
# Define the original bytearray
test_list = [124, 67, 45, 11]
byte_array = bytearray(test_list)
 
# Convert bytearray to hexadecimal string using the struct module
hex_string = ''.join(struct.pack('B', x).hex() for x in byte_array)
 
# Print the result
print("The string before conversion: " + str(test_list))
print("The string after conversion: " + hex_string)

Output

The string before conversion: [124, 67, 45, 11]
The string after conversion: 7c432d0b

Time complexity: O(n), where n is the length of the byte array
Auxiliary Space: O(n), since we are creating a new string to hold the concatenated hexadecimal strings

Using codecs.encode()

Import the codecs module.
Define a list of integers that represent the original bytearray.
Create a bytearray from the list of integers.
Use the codecs.encode() method to convert the bytearray to a hexadecimal string, then decode it to a regular string.
Print the original list of integers and the converted hexadecimal string.

Python3

import codecs
 
#Define the original bytearray
test_list = [124, 67, 45, 11]
byte_array = bytearray(test_list)
 
#Convert bytearray to hexadecimal string using codecs.encode()
hex_string = codecs.encode(byte_array, 'hex').decode()
 
#Print the result
print("The string before conversion: " + str(test_list))
print("The string after conversion: " + hex_string)

Output

The string before conversion: [124, 67, 45, 11]
The string after conversion: 7c432d0b

The time complexity of this code is O(n), where n is the length of the input list.

The auxiliary space of this code is also O(n), as it creates a new bytearray and a new string

Python | Convert Bytearray to Hexadecimal String

Sometimes, we might be in a problem in which we need to handle unusual Datatype conversions. One such conversion can be converting the list of bytes(byte array) to the Hexadecimal string format in Python. Let’s discuss certain Methods in which this can be done.