How to convert string to byte array in Python

user_1024973 0
Viewed 323804

Say that I have a 4 character string, and I want to convert this string into a byte array where each character in the string is translated into its hex equivalent. e.g.

str = "ABCD"

I'm trying to get my output to be 

array('B', [41, 42, 43, 44])

Is there a straightforward way to accomplish this?

python
9 Answers

This work in both Python 2 and 3:

>>> bytearray(b'ABCD')
bytearray(b'ABCD')

Note string started with b.

To get individual chars:

>>> print("DEC HEX ASC")
... for b in bytearray(b'ABCD'):
...     print(b, hex(b), chr(b))
DEC HEX ASC
65 0x41 A
66 0x42 B
67 0x43 C
68 0x44 D

Hope this helps

user_23434880

Depending on your needs, this can be one step or two steps

  1. use encode() to convert string to bytes, immutable
  2. use bytearray() to convert bytes to bytearray, mutable
s="ABCD"
encoded=s.encode('utf-8')
array=bytearray(encoded)

The following validation is done in Python 3.7

>>> s="ABCD"
>>> encoded=s.encode('utf-8')
>>> encoded
b'ABCD'
>>> array=bytearray(encoded)
>>> array
bytearray(b'ABCD')
user_51283980

Since none of the answers is producing exactly array('B', [41, 42, 43, 44]) and the answer by avasal fails in Python 3, I post here my alternative:

import array
s = 'ABCD'
a = array.array('B', [ord(c) for c in s])
print(a)

which prints

array('B', [65, 66, 67, 68])

Note that 65-68 is the correct ASCII for "ABCD".

user_88497550

for python 3 it worked for what @HYRY posted. I needed it for a returned data in a dbus.array. This is the only way it worked

s = "ABCD"

from array import array

a = array("B", s)
user_44492130
Related