TypeError: 'str'不支持缓冲区接口

Question

plaintext = input("Please enter the text you want to compress")
filename = input("Please enter the desired filename")
with gzip.open(filename + ".gz", "wb") as outfile:
    outfile.write(plaintext) 

上面的Python代码给我带来了以下错误：

Traceback (most recent call last):
  File "C:/Users/Ankur Gupta/Desktop/Python_works/gzip_work1.py", line 33, in <module>
    compress_string()
  File "C:/Users/Ankur Gupta/Desktop/Python_works/gzip_work1.py", line 15, in compress_string
    outfile.write(plaintext)
  File "C:\Python32\lib\gzip.py", line 312, in write
    self.crc = zlib.crc32(data, self.crc) & 0xffffffff
TypeError: 'str' does not support the buffer interface

Answer 1

在Python 3中，你不能直接把一个'字符串'转换成字节（bytes），必须先明确地转换成某种编码格式。

outfile.write(plaintext.encode('utf-8'))

这可能就是你想要的。此外，这种方法在Python 2.x和3.x中都适用。

Answer 2

这个问题其实有个更简单的解决办法。

你只需要在模式中加一个 t，这样它就变成 wt 了。这样做会让Python把文件当作文本文件来打开，而不是二进制文件。这样一来，所有的事情就都能正常运行了。

完整的程序变成这样：

plaintext = input("Please enter the text you want to compress")
filename = input("Please enter the desired filename")
with gzip.open(filename + ".gz", "wt") as outfile:
    outfile.write(plaintext)

Answer 3

如果你使用的是Python 3.x，那么string的类型和Python 2.x是不一样的，你需要把它转换成字节（也就是进行编码）。

plaintext = input("Please enter the text you want to compress")
filename = input("Please enter the desired filename")
with gzip.open(filename + ".gz", "wb") as outfile:
    outfile.write(bytes(plaintext, 'UTF-8'))

另外，不要使用像string或file这样的变量名，因为这些都是模块或函数的名称。

编辑 @Tom

是的，非ASCII文本也是可以被压缩和解压缩的。我使用的是带有UTF-8编码的波兰字母：

plaintext = 'Polish text: ąćęłńóśźżĄĆĘŁŃÓŚŹŻ'
filename = 'foo.gz'
with gzip.open(filename, 'wb') as outfile:
    outfile.write(bytes(plaintext, 'UTF-8'))
with gzip.open(filename, 'r') as infile:
    outfile_content = infile.read().decode('UTF-8')
print(outfile_content)