How can I change ascii string to hex and vice versa in python 3.7? - data-conversion

Question

I look some solution in this site but those not works in python 3.7.
So, I asked a new question.
Hex string of "the" is "746865"
I want to a solution to convert "the" to "746865" and "746865" to "the"

Answer 1

Given that your string contains ascii only (each char is in range 0-0xff), you can use the following snippet:
In [28]: s = '746865'
In [29]: import math
In [30]: int(s, base=16).to_bytes(math.ceil(len(s) / 2), byteorder='big').decode('ascii')
Out[30]: 'the'
Firstly you need to convert a string into integer with base of 16, then convert it to bytes (assuming 2 chars per byte) and then convert bytes back to string using decode

Answer 2

#!/usr/bin/python3
"""
Program name: txt_to_ASC.py
The program transfers
a string of letters -> the corresponding
string of hexadecimal ASCII-codes,
eg. the -> 746865
Only letters in [abc...xyzABC...XYZ] should be input.
"""
print("Transfer letters to hex ASCII-codes")
print("Input range is [abc...xyzABC...XYZ].")
print()
string = input("Input set of letters, eg. the: ")
print("hex ASCII-code: " + " "*15, end = "")
def str_to_hasc(x):
global glo
byt = bytes(x, 'utf-8')
bythex = byt.hex()
for b1 in bythex:
y = print(b1, end = "")
glo = str(y)
return glo
str_to_hasc(string)

Answer 3

If you have a byte string, then:
>>> import binascii
>>> binascii.hexlify(b'the')
b'746865'
If you have a Unicode string, you can encode it:
>>> s = 'the'
>>> binascii.hexlify(s)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: a bytes-like object is required, not 'str'
>>> binascii.hexlify(s.encode())
b'746865'
The result is a byte string, you can decode it to get a Unicode string:
>>> binascii.hexlify(s.encode()).decode()
'746865'
The reverse, of course, is:
>>> binascii.unhexlify(b'746865')
b'the'

Answer 4

#!/usr/bin/python3
"""
Program name: ASC_to_txt.py
The program's input is a string of hexadecimal digits.
The string is a bytes object, and each byte is supposed to be
the hex ASCII-code of a (capital or small) letter.
The program's output is the string of the corresponding letters.
Example
Input: 746865
First subresult: ['7','4','6','8','6','5']
Second subresult: ['0x74', '0x68', '0x65']
Third subresult: [116, 104, 101]
Final result: the
References
Contribution by alhelal to stackoverflow.com (20180901)
Contribution by QintenG to stackoverflow.com (20170104)
Mark Pilgrim, Dive into Python 3, section 4.6
"""
import string
print("The program converts a string of hex ASCII-codes")
print("into the corresponding string of letters.")
print("Input range is [41, 42, ..., 5a] U [61, 62, ..., 7a]. \n")
x = input("Input the hex ASCII-codes, eg. 746865: ")
result_1 = []
for i in range(0,len(x)//2):
for j in range(0,2):
result_1.extend(x[2*i+j])
# First subresult
lenres_1 = len(result_1)
result_2 = []
for i in range(0,len(result_1) - 1,2):
temp = ""
temp = temp + "0x" + result_1[i] #0, 2, 4
temp = temp + result_1[i + 1] #1, 3, 5
result_2.append(temp)
# Second subresult
result_3 = []
for i in range(0,len(result_2)):
result_3.append(int(result_2[i],16))
# Third subresult
by = bytes(result_3)
result_4 = by.decode('utf-8')
# Final result
print("Corresponding string of letters:" + " "*6, result_4, end = "\n")