python删除所有的中文字符、非ASCII或非英文字符，检查字符串是否包含非ASCII

Your ''.join() expression is filtering, removing anything non-ASCII; you could use a conditional expression instead:

return ''.join([i if ord(i) < 128 else ' ' for i in text])

This handles characters one by one and would still use one space per character replaced.

Your regular expression should just replace consecutive non-ASCII characters with a space:

re.sub(r'[^\x00-\x7F]+',' ', text)

re.sub(r'[^\x00-\x7f]', ' ', str)

Note the + there.

检查字符串是否包含非英文ASCII等：

a = "ds  dl,;sd!@)~`09历史s"
regexp = re.compile(r'[^\x00-\x7f]')
if regexp.search(a):
  print('matched')