Selenium中CLASS_NAME定位元素失败，如何点击Dismiss弹窗按钮？

问题背景 #

我用Python Selenium操作Investopedia网站，完成登录后始终无法定位并点击弹窗的Dismiss按钮，尝试了三种定位方法均失败，核对过元素HTML结构仍无进展。

我的代码 #

from selenium import webdriver
import os
import time
from selenium.webdriver.common.by import By
from selenium.webdriver.common.action_chains import ActionChains
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

os.environ['PATH'] += r'/usr/local/bin/geckodriver'

browser = webdriver.Firefox()
browser.get('https://www.investopedia.com/auth/realms/investopedia/protocol/openid-connect/auth?client_id=finance-simulator&redirect_uri=https%3A%2F%2Fwww.investopedia.com%2Fsimulator%2Fportfolio&state=84830f95-2e14-4468-87b6-45325beadf2c&response_mode=fragment&response_type=code&scope=openid&nonce=ffc0eff2-93bb-4c25-86f2-f0697898c85b')
browser.set_window_size(1500, 500)

browser.set_window_position(x=0, y=0)

username=browser.find_element(By.ID, "username")
username.send_keys("########")
password = browser.find_element(By.ID, 'password')
password.send_keys('#######')
password.submit()

'''
#First code tried
WebDriverWait(browser, 30).until(
    EC.element_to_be_clickable(
        (By.CLASS_NAME, "pushly_popover-buttons-dismiss pushly-prompt-buttons-dismiss") ,
        
    )
)
'''
'''
#Second code tried
time.sleep(35)
popup = browser.find_element(By.CLASS_NAME, "pushly_popover-buttons-dismiss pushly-prompt-buttons-dismiss")
'''
#Third code tried
time.sleep(35)
popup = browser.find_element(By.XPATH,"//span[text()='Dismiss']")
popup.click()

遇到的错误 #

#First tried
raise TimeoutException(message, screen, stacktrace)
selenium.common.exceptions.TimeoutException: Message: 
Stacktrace:
WebDriverError@chrome://remote/content/shared/webdriver/Errors.jsm:188:5
NoSuchElementError@chrome://remote/content/shared/webdriver/Errors.jsm:400:5
element.find/</<@chrome://remote/content/marionette/element.js:292:16

#Second tried
raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.NoSuchElementException: Message: Unable to locate element: .pushly_popover-buttons-dismiss pushly-prompt-buttons-dismiss
Stacktrace:
WebDriverError@chrome://remote/content/shared/webdriver/Errors.jsm:188:5
NoSuchElementError@chrome://remote/content/shared/webdriver/Errors.jsm:400:5
element.find/</<@chrome://remote/content/marionette/element.js:292:16


#third tried
raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.NoSuchElementException: Message: Unable to locate element: //span[text()='Dismiss']

解决方案 #

核心问题分析 #

1. By.CLASS_NAME用法错误：该方法只能传入单个类名，多个类名需用By.CSS_SELECTOR，类名之间用.连接
2. 弹窗在独立iframe中：Pushly这类第三方弹窗通常会放在单独的iframe里，Selenium默认在主文档查找元素，必须先切换到对应iframe才能定位
3. time.sleep()不可靠：固定等待时间无法适配页面加载速度，显式等待能确保元素可操作后再执行点击

修正后的代码 #

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

os.environ['PATH'] += r'/usr/local/bin/geckodriver'

browser = webdriver.Firefox()
browser.get('https://www.investopedia.com/auth/realms/investopedia/protocol/openid-connect/auth?client_id=finance-simulator&redirect_uri=https%3A%2F%2Fwww.investopedia.com%2Fsimulator%2Fportfolio&state=84830f95-2e14-4468-87b6-45325beadf2c&response_mode=fragment&response_type=code&scope=openid&nonce=ffc0eff2-93bb-4c25-86f2-f0697898c85b')
browser.set_window_size(1500, 500)
browser.set_window_position(x=0, y=0)

# 登录操作
username = browser.find_element(By.ID, "username")
username.send_keys("########")
password = browser.find_element(By.ID, 'password')
password.send_keys('#######')
password.submit()

try:
    # 切换到弹窗所在的iframe
    WebDriverWait(browser, 20).until(
        EC.frame_to_be_available_and_switch_to_it((By.CSS_SELECTOR, "iframe[src*='pushly']"))
    )
    
    # 显式等待并定位Dismiss按钮
    dismiss_btn = WebDriverWait(browser, 20).until(
        EC.element_to_be_clickable((By.CSS_SELECTOR, ".pushly_popover-buttons-dismiss.pushly-prompt-buttons-dismiss"))
    )
    dismiss_btn.click()
    
    # 切换回主文档
    browser.switch_to.default_content()
except Exception as e:
    print(f"处理弹窗时出错: {e}")

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