Selenium在while循环第二次执行时抛出WebDriverException问题求助

问题描述 #

运行以下Selenium代码时，首次while循环可正常执行，但第二次循环时程序崩溃并抛出错误，预期输出的“Factory purchased”日志未出现：

import time

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

game_mins = 5
play_seconds = 5

chrome_driver_path = "your own chrome driver address here"
ser = Service(executable_path=chrome_driver_path)
driver = webdriver.Chrome(service=ser)

driver.get("http://orteil.dashnet.org/experiments/cookie/")

cookie = driver.find_element(By.ID, "cookie")

Most_expensive = driver.find_element(By.ID, "buyTime machine")
Second_expensive = driver.find_element(By.ID, "buyPortal")
Third_expensive = driver.find_element(By.ID, "buyAlchemy lab")
Fourth_expensive = driver.find_element(By.ID, "buyShipment")
Fifth_expensive = driver.find_element(By.ID, "buyMine")
Sixth_expensive = driver.find_element(By.ID, "buyFactory")
Seventh_expensive = driver.find_element(By.ID, "buyGrandma")
Eighth_expensive = driver.find_element(By.ID, "buyCursor")

game_end = time.time() + game_mins * 60

while time.time() < game_end:
    t_end = time.time() + play_seconds
    while time.time() < t_end:
        cookie.click()

    print("Moving on to the ifs statement")
    time.sleep(4)

    if Most_expensive.get_attribute("class") != "grayed":
        print("Time machine purchased")
        Most_expensive.click()
    elif Second_expensive.get_attribute("class") != "grayed":
        print("Portal purchased")
        Second_expensive.click()
    elif Third_expensive.get_attribute("class") != "grayed":
        print("Alchemy lab purchased")
        Third_expensive.click()
    elif Fourth_expensive.get_attribute("class") != "grayed":
        print("Shipment purchased")
        Fourth_expensive.click()
    elif Fifth_expensive.get_attribute("class") != "grayed":
        print("Mine purchased")
        Fifth_expensive.click()
    elif Sixth_expensive.get_attribute("class") != "grayed":
        print("Factory purchased")
        Sixth_expensive.click()
    elif Seventh_expensive.get_attribute("class") != "grayed":
        print("Granma purchased")
        Seventh_expensive.click()
    else:
        print("Cursor purchased")
        Eighth_expensive.click()

time.sleep(50)

控制台输出的错误信息：

Moving on to the ifs statement
Granma purchased
Moving on to the ifs statement

selenium.common.exceptions.WebDriverException: 
Message: unknown error: 
unhandled inspector error: 
{"code":-32000,"message":"No node with given id found"}

问题根源 #

错误核心是失效元素引用（Stale Element Reference）：

• 程序启动时一次性获取了所有物品元素的引用
• 购买物品后页面DOM结构会更新（比如物品状态、价格变化），之前的元素引用会失效，Selenium无法找到对应DOM节点，从而抛出"No node with given id found"错误

解决方案 #

每次循环时重新获取所有物品元素的引用，确保操作的是当前页面的有效DOM元素。同时优化逻辑，用列表存储物品优先级，避免冗长的elif判断：

import time

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

game_mins = 5
play_seconds = 5

chrome_driver_path = "your own chrome driver address here"
ser = Service(executable_path=chrome_driver_path)
driver = webdriver.Chrome(service=ser)

driver.get("http://orteil.dashnet.org/experiments/cookie/")

game_end = time.time() + game_mins * 60

# 按优先级从高到低定义物品ID和名称
items = [
    ("buyTime machine", "Time machine"),
    ("buyPortal", "Portal"),
    ("buyAlchemy lab", "Alchemy lab"),
    ("buyShipment", "Shipment"),
    ("buyMine", "Mine"),
    ("buyFactory", "Factory"),
    ("buyGrandma", "Grandma"),
    ("buyCursor", "Cursor")
]

while time.time() < game_end:
    # 每次循环重新获取cookie元素（保险起见，避免DOM更新导致引用失效）
    cookie = driver.find_element(By.ID, "cookie")
    t_end = time.time() + play_seconds
    while time.time() < t_end:
        cookie.click()

    print("Moving on to the ifs statement")
    time.sleep(4)

    # 遍历物品列表，找到第一个可购买的（未被grayed的）
    purchased = False
    for item_id, item_name in items:
        try:
            item = driver.find_element(By.ID, item_id)
            if item.get_attribute("class") != "grayed":
                print(f"{item_name} purchased")
                item.click()
                purchased = True
                break
        except Exception as e:
            # 处理元素暂时找不到的情况（比如页面加载延迟）
            continue
    if not purchased:
        print("No affordable items found")

time.sleep(50)
driver.quit()  # 关闭浏览器释放资源

关键优化点 #

• 实时获取元素：每次循环重新查找物品元素，避免引用失效
• 简化逻辑：用列表存储物品优先级，通过循环替代冗长的elif判断，代码更易维护
• 异常处理：添加try-except捕获元素查找时的临时异常，提升程序稳定性
• 资源清理：最后调用driver.quit()关闭浏览器，释放系统资源

内容的提问来源于stack exchange，提问作者MakT