Selenium 通过 class 查找元素，但 returns 为空字符串。怎么修？

Question

该代码试图显示一个城市的天气预报。它能够找到包含内容的 class，但它打印出一个空字符串。为什么会这样？我该如何更改我的代码以不获取空字符串？

from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from selenium.webdriver.common.by import By

s=Service("C:\Program Files (x86)\chromedriver.exe")
browser = webdriver.Chrome(service=s)

city = str(input("Enter a city"))

url="https://www.weather-forecast.com/locations/"+city+"/forecasts/latest"
browser.get(url)
browser.maximize_window()

content = browser.find_element(By.CLASS_NAME, "b-forecast__table-description-content")
print(content.text)

Answer 1

你已经足够接近了。内容实际上在祖先 <p> 标签的后代 <span> 内。

要打印所有需要的文本，您必须诱导 for the visibility_of_all_elements_located() and you can use either of the following :

使用CSS_SELECTOR:

city = "Dallas"
driver.get("https://www.weather-forecast.com/locations/"+city+"/forecasts/latest")
print([my_elem.text for my_elem in WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.CSS_SELECTOR, "p.b-forecast__table-description-content > span.phrase")))])

使用 XPATH:

city = "Dallas"
driver.get("https://www.weather-forecast.com/locations/"+city+"/forecasts/latest")
print([my_elem.get_attribute("innerText") for my_elem in WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.XPATH, "//p[@class='b-forecast__table-description-content']/span[@class='phrase']")))])

控制台输出：

['Heavy rain (total 0.8in), heaviest during Tue night. Warm (max 86°F on Mon afternoon, min 66°F on Tue night). Winds decreasing (fresh winds from the S on Sun night, light winds from the S by Mon night).', 'Light rain (total 0.3in), mostly falling on Fri morning. Warm (max 77°F on Wed afternoon, min 57°F on Wed night). Wind will be generally light.', 'Light rain (total 0.1in), mostly falling on Sat night. Warm (max 84°F on Sat afternoon, min 43°F on Sun night). Winds decreasing (fresh winds from the N on Sun afternoon, calm by Mon night).', 'Mostly dry. Warm (max 70°F on Wed afternoon, min 48°F on Tue night). Wind will be generally light.']

注意：您必须添加以下导入：

from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions as EC

Selenium 通过 class 查找元素，但 returns 为空字符串。怎么修？

Selenium finds element by class, but returns empty string. How to fix?

python

selenium

xpath

css-selectors

webdriverwait