python - 如何从 STDOUT 编辑字符串

Question

我有这个代码:

netshcmd = subprocess.Popen('netsh wlan stop hostednetwork', shell=True, stderr=subprocess.PIPE, stdout=subprocess.PIPE)
output, errors = netshcmd.communicate()
if errors:
    print("Warrning: ", errors)
else:
    print("Success", output)

输出是这样的:

Success b'The hosted network stopped. \r\n\r\n'

如何获得像这样的输出“成功托管网络已停止。”？

Answer 1

从子进程读取会得到一个字节串。您可以解码此字节字符串(您必须找到合适的编码)，或者使用 universal_newlines 选项并让 Python 自动为您解码:

netshcmd = subprocess.Popen(
    'netsh wlan stop hostednetwork', 
    shell=True, stderr=subprocess.PIPE, stdout=subprocess.PIPE,
    universal_newlines=True)

来自Frequently Used Arguments documentation section :

If universal_newlines is True, these file objects will be opened as text streams in universal newlines mode using the encoding returned by locale.getpreferredencoding(False). For stdin, line ending characters '\n' in the input will be converted to the default line separator os.linesep. For stdout and stderr, all line endings in the output will be converted to '\n'. For more information see the documentation of the io.TextIOWrapper class when the newline argument to its constructor is None.

对于通过 shell 运行的进程，locale.getpreferredencoding(False) 应该完全使用正确的编解码器，因为它获取有关要使用的编码的信息locale environment variables 与 netsh 等其他进程应该引用的位置完全相同。 .

使用universal_newlines=True，output将设置为字符串'托管网络已停止。\n\n'；请注意末尾的换行符。您可能需要使用str.strip()`来删除那里多余的空格:

print("Success", output.strip())