Question

我是python 3的新手，它试图从包含消息中字符串和字节的字节数组中提取消息。

我无法从解码的字节数组中提取字节消息。

首先，我解码bytes数组。
然后我对解码后的数组进行拆分。
拆分数组后会得到字符串值。

我尝试使用bytes(v) for v in rest.split()函数尝试获取bytes数组，然后对其进行解码，但无法。

# The message chunk:
chunk = b"1568077849\n522\nb'l5:d4:auth53:\xc3\x99\xc3\xac\x1fH\xc2\xa3ei6eli1eee'\n"

# I split the chunk into sub categories for further processing:
_, size, rest = (chunk.decode("utf-8")).split('\n', 2)

# _ contains "1568077849"
# size contains "522" 
# rest contains "b'l5:d4:auth53:\xc3\x99\xc3\xac\x1fH\xc2\xa3ei6eli1eee'"

我应该能够解码rest变量（rest.decode（“ utf-8”）），但是由于它已经以字符串形式存储，所以我很难弄清楚如何转换它到字节，然后将值解码。

预期结果：l5:d4:auth53:ÙìH£ei6eli1eee

Answer 1

这将打印您的最终结果：

chunk = b"1568077849\n522\nb'l5:d4:auth53:\xc3\x99\xc3\xac\x1fH\xc2\xa3ei6eli1eee'\n"

l1 = chunk.decode('utf-8').split()[2:]  # Initial decode
#  slice out the embedded byte string "b'  '" characters
l1_string = ''.join([x[:-2] if x[0] != 'b' else x[2:] for x in l1])
l1_bytes = l1_string.encode('utf-8')
l1_final = l1_bytes.decode('utf-8')

print('Results')
print(f'l1_string is {l1_string}')
print(f'l1_bytes is {l1_bytes}')
print(f'l1_final is {l1_final}')

Results
l1_string is l5:d4:auth53:ÙìH£ei6eli1ee
l1_bytes is b'l5:d4:auth53:\xc3\x99\xc3\xacH\xc2\xa3ei6eli1ee'
l1_final is l5:d4:auth53:ÙìH£ei6eli1ee

Answer 2

我能够通过这种方式获得预期的输出：

 _, size, rest = (chunk.decode("utf-8")).split('\n', 2)
 rest = bytes(rest.replace("b'", "").replace("'", ""), "utf-8").decode("unicode_escape")

从这篇文章中得到了线索： Process escape sequences in a string in Python

从包含字节数据的字符串中提取字节

2 个答案: