需要帮助尝试识别页面的用户名部分和 pw 部分（python selenium）答案

【问题标题】：Need Help Trying to identify the username section and pw section of a page (python selenium)需要帮助尝试识别页面的用户名部分和 pw 部分（python selenium）
【发布时间】：2020-08-17 12:25:17
【问题描述】：

我本质上是 scraping chegg，我需要帮助来尝试识别 css id="emailForSignIn" 我正在尝试找到一种方法来检测登录部分的文本栏在 chegg 登录页面的位置

下面是实现的功能：

def signin():  # Only use this function if you are using new instances of your browser each time
    print('>>signing in!')
    browser.get('https://www.chegg.com/auth?action=login&redirect=https%3A%2F%2Fwww.chegg.com%2F')
    handle_captcha()

    time.sleep(2)
    email_elem = browser.find_element_by_id('emailForSignIn')
    for character in 'alondra_calderon@ymail.com':
        email_elem.send_keys(character)
        time.sleep(0.1)
    time.sleep(2)

    password_elem = browser.find_element_by_id('passwordForSignIn')
    for character in 'Blueyes97':
        password_elem.send_keys(character)
        time.sleep(0.1)
    time.sleep(2)

    browser.find_element_by_name('login').click()

    try:
        if WebDriverWait(browser, 5).until(EC.presence_of_element_located((By.XPATH, "/html/body/div[1]/div[3]/div[2]/div[2]/div/div[3]/div/oc-component/div/div/div/div[2]/div[1]/div[1]/div/form/div/div/div/div/div[3]/span"))):
            print('redirecting back to login')
            browser.get('https://www.chegg.com/auth?action=login')
            handle_captcha()
            signin()
            handle_captcha()
    except TimeoutException:
        pass

    if browser.find_element_by_tag_name('h1').text == 'Oops, we\'re sorry!':
        return [0]
    handle_captcha()

以下是错误：

PS C:\Users\Dami\Desktop\chegg_discord_bot-master>  & 'C:\Program Files (x86)\Python38-32\python.exe' 'c:\Users\Dami\.vscode\extensions\ms-python.python-2020.8.101144\pythonFiles\lib\python\debugpy\launcher' '58627' '--' 'c:\Users\Dami\Desktop\cheggDiscordBot.py'

DevTools listening on ws://127.0.0.1:58638/devtools/browser/837850c8-796e-44be-950f-49f667f48f0a
>>signing in!
Traceback (most recent call last):
  File "c:\Users\Dami\Desktop\cheggDiscordBot.py", line 288, in <module>
    signin()
  File "c:\Users\Dami\Desktop\cheggDiscordBot.py", line 257, in signin
    email_elem = browser.find_element_by_id('emailForSignIn')
  File "C:\Users\Dami\AppData\Roaming\Python\Python38\site-packages\selenium\webdriver\remote\webdriver.py", 
line 360, in find_element_by_id
    return self.find_element(by=By.ID, value=id_)
  File "C:\Users\Dami\AppData\Roaming\Python\Python38\site-packages\selenium\webdriver\remote\webdriver.py", 
line 976, in find_element
    return self.execute(Command.FIND_ELEMENT, {
  File "C:\Users\Dami\AppData\Roaming\Python\Python38\site-packages\selenium\webdriver\remote\webdriver.py", 
line 321, in execute
    self.error_handler.check_response(response)
  File "C:\Users\Dami\AppData\Roaming\Python\Python38\site-packages\selenium\webdriver\remote\errorhandler.py", line 242, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.NoSuchElementException: Message: no such element: Unable to locate element: {"method":"css selector","selector":"[id="emailForSignIn"]"}
  (Session info: headless chrome=84.0.4147.125)

【问题讨论】：

我不确定您的验证码处理方法是否能够导航到电子邮件/密码输入页面。因为我看不到定位器有任何问题。请检查验证码是否处理不当。

标签： python selenium xpath css-selectors webdriverwait

【解决方案1】：

要将字符序列发送到电子邮件和密码字段，您必须为element_to_be_clickable()诱导WebDriverWait，您可以使用以下任一Locator Strategies:

使用CSS_SELECTOR：

driver.get('https://www.chegg.com/auth?action=login&redirect=https%3A%2F%2Fwww.chegg.com%2F')
WebDriverWait(driver, 20).until(EC.element_to_be_clickable((By.CSS_SELECTOR, "input#emailForSignIn"))).send_keys("alondra_calderon@ymail.com")
driver.find_element_by_css_selector("input#passwordForSignIn").send_keys("passwordForSignIn")

使用XPATH：

driver.get('https://www.chegg.com/auth?action=login&redirect=https%3A%2F%2Fwww.chegg.com%2F')
WebDriverWait(driver, 20).until(EC.element_to_be_clickable((By.XPATH, "//input[@id='emailForSignIn']"))).send_keys("alondra_calderon@ymail.com")
driver.find_element_by_xpath("//input[@id='passwordForSignIn']").send_keys("passwordForSignIn")

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

浏览器快照：

【讨论】：

【解决方案2】：

似乎同步问题如下错误指示-

无法定位元素：{"method":"css 选择器","选择器":"[id="emailForSignIn"]"}

在您的脚本中引入显式等待并更改您的代码，如下所示：

WebDriverWait(driver, 10).until(EC.visibility_of_element_located((By.ID, "emailForSignIn"))).send_keys("alondra_calderon@ymail.com")
WebDriverWait(driver, 10).until(EC.visibility_of_element_located((By.ID, "passwordForSignIn"))).send_keys("Blueyes97")
driver.find_element_by_name('login').click()

注意：无需遍历电子邮件和密码 Selenium 自动以相同方式输入文本

为此导入以下软件包：

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

【讨论】：