Python 3-将2位整数与2个字符的十六进制等效进行相互转换

Question

I have researched this and while I could find some methods to convert a string consisting of a 3-digit integer to a string consisting of its 2-digit hex equivalent, I did not find a way to convert the 2-digit-hex string back into the original 3-digit integer.

For example, I would like to convert "015" to its 2-digit hex equivalent "0F" and vice versa.

Another example: "123" to "7B" and "7B" to "123".

I would prefer separate methods for these two conversions, rather than 1 function that can take either type of string and return the other.

# Method I'm currently using to convert int to hex:
myHex = str(format(int(myNumber), '02x'))
print("Integer " + myNumber + " converted to " + myHex)

Your help is greatly appreciated.

Answer 1

you can use:

1) build in hex method

hex(int('123')) --> '0x7b'
str(int('0x7b', 16)) --> '123'

if you do not want '0x' part:

hex(int('123'))[2:] --> '7b'
str(int('7b', 16)) --> '123'

or :

2) using fstring

def str_to_hex(my_str_num):
    return f'{int(my_str_num):02x}'

def hex_to_str(my_hex):
    return f'{int(my_hex, 16):>03}'

print(str_to_hex('015'))
print(hex_to_str('0f'))

print(str_to_hex('123'))
print(hex_to_str('7b'))

output:

0f
015

7b
123

Answer 2

You can use the following function:

def two_digit_hex_to_three_digit_integer(hex):
    return str(int(hex, 16)).zfill(3)

Explanation:

int(hex, 16) will convert your two-digit hex number into an int of base 10. Then, this will be converted to str , and it will be filled with up to 3 zeros to satisfy the condition you said of three-digit integer.

Usage:

>>> two_digit_hex_to_three_digit_integer('7B')
'123'
>>> two_digit_hex_to_three_digit_integer('0F')
'015'

Answer 3

For base-10 to base-16 conversion you can harness str formatting following way:

def convert_dec_to_hex(value):
    return "%X" % int(value)
print(convert_dec_to_hex("123")) # 7B

uppercase X gives ABCDEF and lowercase x gives abcdef so

def convert_dec_to_hex(value):
    return "%X" % int(value)
print(convert_dec_to_hex("123")) # 7b