Question

我将数据存储在字节数组中。如何将此数据转换为十六进制字符串？

我的字节数组示例：

array_alpha = [ 133, 53, 234, 241 ]

Answer 1

使用str.format：

>>> array_alpha = [ 133, 53, 234, 241 ]
>>> print ''.join('{:02x}'.format(x) for x in array_alpha)
8535eaf1

或使用format

>>> print ''.join(format(x, '02x') for x in array_alpha)
8535eaf1

注意：在格式声明中，02表示如有必要，它最多会填充2个前导0。这很重要，因为[0x1, 0x1, 0x1] i.e. (0x010101)格式为"111"而不是"010101"

或将bytearray与binascii.hexlify一起使用：

>>> import binascii
>>> binascii.hexlify(bytearray(array_alpha))
'8535eaf1'

以下是Python 3.6.1中上述方法的基准：

from timeit import timeit
import binascii

number = 10000

def using_str_format() -> str:
    return "".join("{:02x}".format(x) for x in test_obj)

def using_format() -> str:
    return "".join(format(x, "02x") for x in test_obj)

def using_hexlify() -> str:
    return binascii.hexlify(bytearray(test_obj)).decode('ascii')

def do_test():
    print("Testing with {}-byte {}:".format(len(test_obj), test_obj.__class__.__name__))
    if using_str_format() != using_format() != using_hexlify():
        raise RuntimeError("Results are not the same")

    print("Using str.format       -> " + str(timeit(using_str_format, number=number)))
    print("Using format           -> " + str(timeit(using_format, number=number)))
    print("Using binascii.hexlify -> " + str(timeit(using_hexlify, number=number)))

test_obj = bytes([i for i in range(255)])
do_test()

test_obj = bytearray([i for i in range(255)])
do_test()

结果：

Testing with 255-byte bytes:
Using str.format       -> 1.459474583090427
Using format           -> 1.5809937679100738
Using binascii.hexlify -> 0.014521426401399307
Testing with 255-byte bytearray:
Using str.format       -> 1.443447684109402
Using format           -> 1.5608712609513171
Using binascii.hexlify -> 0.014114164661833684

使用format的方法确实提供了其他格式选项，例如用空格" ".join，逗号", ".join，大写打印"{:02X}".format(x) / format(x, "02X")分隔数字等，但代价是性能影响很大。

Answer 2

考虑Python 3.5及更高版本的bytes类型的hex() method：

>>> array_alpha = [ 133, 53, 234, 241 ]
>>> print(bytes(array_alpha).hex())
8535eaf1

编辑：它也比hexlify快得多（修改后的@fattru＆＃39基准）

from timeit import timeit
N = 10000
print("bytearray + hexlify ->", timeit(
    'binascii.hexlify(data).decode("ascii")',
    setup='import binascii; data = bytearray(range(255))',
    number=N,
))
print("byte + hex          ->", timeit(
    'data.hex()',
    setup='data = bytes(range(255))',
    number=N,
))

结果：

bytearray + hexlify -> 0.011218150997592602
byte + hex          -> 0.005952142993919551

Answer 3

hex_string = "".join("%02x" % b for b in array_alpha)

Answer 4

如果你有一个numpy数组，你可以执行以下操作：

>>> import numpy as np
>>> a = np.array([133, 53, 234, 241])
>>> a.astype(np.uint8).data.hex()
'8535eaf1'

Answer 5

或者，如果您是函数式编程的粉丝：

>>> a = [133, 53, 234, 241]
>>> "".join(map(lambda b: format(b, "02x"), a))
8535eaf1
>>>

字节数组到十六进制字符串

5 个答案: