使用Beautiful Soup提取数据返回None的技术求助

Hey there! Let's break down why your current code isn't pulling the real-time parking spot data you want, and fix it up.

The Core Issue: Wrong Target Structure #

First up—you're trying to look for <span class="text"> elements, but the URL you're hitting returns XML data, not HTML. That's why your find_all calls are coming back empty or None—those span tags don't exist in the XML response at all.

If you run print(soup.prettify()), you'll see the actual structure looks something like this (simplified):

<sign_data>
  <signID id="some-id">
    <Display>123</Display>
    <!-- Other tags -->
  </signID>
  <signID id="another-id">
    <Display>45</Display>
    <!-- Other tags -->
  </signID>
</sign_data>

Corrected Code to Extract Display Values #

Since we're working with XML, we can directly target the signID and Display tags. Here's the adjusted code:

import requests
import bs4

# Fetch the XML data
res = requests.get('https://www.jmu.edu/cgi-bin/parking_sign_data.cgi?hash=53616c7465645f5f5c0bbd0eccccb6fe8dd7ed9a0445247e3c7dcb4f91927f7ccc933be780c6e558afb8ebf73620c3e5e3b2c68cd3c138519068eac99d9bf30e1e67ce894deb3a054f95f882da2ea2f0|869835tg89dhkdnbnsv5sg5wg0vmcf4mfcfc2qwm5968unmeh5')
res.encoding = 'utf-8'  # Ensure proper character encoding
soup = bs4.BeautifulSoup(res.text, 'xml')

# Extract all Display values from signID tags
all_signs = soup.find_all('signID')
for sign in all_signs:
    display_value = sign.find('Display').text
    print(f"Available Spots: {display_value}")

# To target only the Commuter Parking section:
# First, check the 'id' attribute of each signID to find the one matching commuter parking
# Uncomment the lines below to list all sign IDs:
# for sign in all_signs:
#     print(f"Sign ID: {sign.get('id')}")
# Then use that ID to filter:
# commuter_sign = soup.find('signID', id='your-commuter-id')
# if commuter_sign:
#     commuter_spots = commuter_sign.find('Display').text
#     print(f"Commuter Parking Spots Left: {commuter_spots}")

Key Notes #

• Always verify the response format first—using print(soup.prettify()) will show you exactly what tags and structure you're working with.
• The XML updates every second, so your script will pull the latest real-time data each time it runs.

内容的提问来源于stack exchange，提问作者Ivan Jackson