TypeError:'str'不支持缓冲区接口

Question

import hashlib

infile = open("P:\\r.mp3", 'r+b')
data = infile.readline()
hash = hashlib.md5()
hash.update(data)

hash_digest = hash.hexdigest()
print(hash_digest)
#hash_digest = hash_digest.encode('utf-8')
print(hash_digest)
with open("lt.txt", 'ab') as outfile:
    outfile.write(hash_digest + '\n')   #error here

with open("syncDB.txt", 'rb') as fg:
    for data in fg:
    print(data)

outfile.write(hash_digest + '\n')
TypeError: 'str' does not support the buffer interface

我如何纠正这一点以及在这些情况下我需要学习什么才能看到我？

此外,如果我在utf-8(取消注释)中对此进行编码,则会发出以下错误:

TypeError: can't concat bytes to str

Answer 1

您正在使用Python 3,其中text(str)和data(bytes)之间存在严格的划分.如果您没有先对文本进行显式编码,则无法将文本写入文件.

有两种方法可以做到这一点:

1)以文本模式打开文件(可能指定了编码),以便为您自动编码字符串:

with open("lt.txt", 'at', encoding='utf8') as outfile:
    outfile.write(hash_digest + '\n') # or print(hash_digest, file=outfile)

如果在文本模式下打开文件时未自行指定编码,则将使用系统区域设置的默认编码.

2)像你尝试的那样手动编码字符串.但是,不要尝试混合str与bytes像你这样,既可以使用一个字节的文字:

hash_digest = hash_digest.encode('utf-8')
with open("lt.txt", 'ab') as outfile:
    outfile.write(hash_digest + b'\n')   # note the b for bytes

或者在添加换行符后进行编码:

    outfile.write((hash_digest + '\n').encode('utf-8'))