Question

目前我正在尝试阅读网页，然后处理内容，但我还想实现客户端离线时的异常处理。这是我到目前为止的代码：

from urllib.request import Request, urlopen
from lxml import html




def get_webSite(link):  # returns a HTML page which can be read by the xPath
    req = Request(link, headers={'User-Agent': 'Mozilla/5.0'})
    return html.fromstring(urlopen(req).read())





try:
    htmlPage = get_webSite("www.example.com")
    print(htmlPage)
except urllib.error.URLError as e:
    print("You're offline, try again later")

问题是 python 似乎无法识别“urllib.error.URLError”，如果没有互联网连接，则会抛出该错误。 Intellij 总是告诉我“未解析的引用 urllib”

这是没有任何互联网连接的控制台的输出：

"C:\Program Files\Python39\py

thon.exe" C:/test/test.py
Traceback (most recent call last):
  File "C:\Program Files\Python39\lib\urllib\request.py", line 1342, in do_open
    h.request(req.get_method(), req.selector, req.data, headers,
  File "C:\Program Files\Python39\lib\http\client.py", line 1255, in request
    self._send_request(method, url, body, headers, encode_chunked)
  File "C:\Program Files\Python39\lib\http\client.py", line 1301, in _send_request
    self.endheaders(body, encode_chunked=encode_chunked)
  File "C:\Program Files\Python39\lib\http\client.py", line 1250, in endheaders
    self._send_output(message_body, encode_chunked=encode_chunked)
  File "C:\Program Files\Python39\lib\http\client.py", line 1010, in _send_output
    self.send(msg)
  File "C:\Program Files\Python39\lib\http\client.py", line 950, in send
    self.connect()
  File "C:\Program Files\Python39\lib\http\client.py", line 1417, in connect
    super().connect()
  File "C:\Program Files\Python39\lib\http\client.py", line 921, in connect
    self.sock = self._create_connection(
  File "C:\Program Files\Python39\lib\socket.py", line 822, in create_connection
    for res in getaddrinfo(host, port, 0, SOCK_STREAM):
  File "C:\Program Files\Python39\lib\socket.py", line 953, in getaddrinfo
    for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
socket.gaierror: [Errno 11001] getaddrinfo failed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:/test/test.py", line 17, in <module>
    htmlPage = get_webSite("https://www.google.com")
  File "C:/test/test.py", line 10, in get_webSite
    return html.fromstring(urlopen(req).read())
  File "C:\Program Files\Python39\lib\urllib\request.py", line 214, in urlopen
    return opener.open(url, data, timeout)
  File "C:\Program Files\Python39\lib\urllib\request.py", line 517, in open
    response = self._open(req, data)
  File "C:\Program Files\Python39\lib\urllib\request.py", line 534, in _open
    result = self._call_chain(self.handle_open, protocol, protocol +
  File "C:\Program Files\Python39\lib\urllib\request.py", line 494, in _call_chain
    result = func(*args)
  File "C:\Program Files\Python39\lib\urllib\request.py", line 1385, in https_open
    return self.do_open(http.client.HTTPSConnection, req,
  File "C:\Program Files\Python39\lib\urllib\request.py", line 1345, in do_open
    raise URLError(err)
urllib.error.URLError: <urlopen error [Errno 11001] getaddrinfo failed>

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:/test/test.py", line 19, in <module>
    except urllib.error.URLError as e:
NameError: name 'urllib' is not defined

Process finished with exit code 1

我只能用“except:”捕捉这个错误，但不能用“except urllib.error.URLError:”捕捉到这个错误。我该如何解决？

Answer 1

您导入了 urllib.request。然后您的程序不知道 urllib.error，因为它不包含在 urllib.request 中。
import urllib 或 import urllib.error 应该可以解决问题。

异常处理导致“未解析的引用”python

1 个答案: