无法使用 Python Selenium WebDriver 正确访问元素

Question

所以我正在学习如何使用 Selenium 进行 Web 自动化 - 我正在尝试编写一个脚本，returns 我的美国运通余额到我的控制台。第一步其实是登录成功...

我点击登录按钮的操作似乎引发了找不到该元素的错误，即使我在 firebug 时可以看到它。

这是我的代码：

from selenium import webdriver

driver = webdriver.Firefox()

baseurl = "https://www.americanexpress.com/canada/"
username = "myusername"
password = "mypassword"

xpaths = { 'usernameField' : "//input[@id='UserID']",
           'passwordField' : "//input[@id='Password']",
           'submitButton' :   "//input[@id='loginButton']"
         }

driver.get(baseurl)

driver.find_element_by_xpath(xpaths['usernameField']).clear()

driver.find_element_by_xpath(xpaths['usernameField']).send_keys(username)

driver.find_element_by_xpath(xpaths['passwordField']).clear()

driver.find_element_by_xpath(xpaths['passwordField']).send_keys(password)

driver.find_element_by_xpath(xpaths['submitButton']).click()

这是我收到的控制台错误消息，浏览器已经填写了我的登录详细信息，但还没有点击登录按钮：

Traceback (most recent call last):
  File "get_balance.py", line 29, in <module>
    driver.find_element_by_xpath(xpaths['submitButton']).click()
  File "/Library/Python/2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 232, in find_element_by_xpath
    return self.find_element(by=By.XPATH, value=xpath)
  File "/Library/Python/2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 664, in find_element
    {'using': by, 'value': value})['value']
  File "/Library/Python/2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 175, in execute
    self.error_handler.check_response(response)
  File "/Library/Python/2.7/site-packages/selenium/webdriver/remote/errorhandler.py", line 166, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.NoSuchElementException: Message: Unable to locate element: {"method":"xpath","selector":"//input[@id='loginButton']"}
Stacktrace:
    at FirefoxDriver.prototype.findElementInternal_ (file:///var/folders/mx/dbnsd72j05zd4k2cls4cvmf00000gn/T/tmpKQDaey/extensions/fxdriver@googlecode.com/components/driver-component.js:10271)
    at FirefoxDriver.prototype.findElement (file:///var/folders/mx/dbnsd72j05zd4k2cls4cvmf00000gn/T/tmpKQDaey/extensions/fxdriver@googlecode.com/components/driver-component.js:10280)
    at DelayedCommand.prototype.executeInternal_/h (file:///var/folders/mx/dbnsd72j05zd4k2cls4cvmf00000gn/T/tmpKQDaey/extensions/fxdriver@googlecode.com/components/command-processor.js:12274)
    at DelayedCommand.prototype.executeInternal_ (file:///var/folders/mx/dbnsd72j05zd4k2cls4cvmf00000gn/T/tmpKQDaey/extensions/fxdriver@googlecode.com/components/command-processor.js:12279)
    at DelayedCommand.prototype.execute/< (file:///var/folders/mx/dbnsd72j05zd4k2cls4cvmf00000gn/T/tmpKQDaey/extensions/fxdriver@googlecode.com/components/command-processor.js:12221)

有什么想法吗？非常感谢任何 advice/help，谢谢！

Answer 1

这是一个 a 元素，而不是 input:

<a tabindex="0" href="#" id="loginButton" title="Login securely">
    <span></span>
    Log In
</a>

将您的 xpath 更改为：//a[@id="loginButton"]。

除此之外，对于 id 属性，有一个 find_element_by_id() 方法：

driver.find_element_by_id("loginButton").click()

此外，如果您希望将元素定位器与实际 "action" 代码分开，您可以按以下方式配置它（为了示例，留下一个 xpath 表达式）：

from selenium.webdriver.common.by import By

locators = { 
    'usernameField': (By.ID, "UserID"),
    'passwordField': (By.XPATH, "//input[@id='Password']"),
    'submitButton': (By.ID, "loginButton")
}

然后，您的 "action" 代码将使用 find_element():

username = driver.find_element(*locators['usernameField'])
username.clear()
username.send_keys(username)

password = driver.find_element(*locators['passwordField'])
password.clear()
password.send_keys(password)

login_button = driver.find_element(*locators['submitButton'])
login_button.click()

无法使用 Python Selenium WebDriver 正确访问元素

Can't properly access element using Python Selenium WebDriver

python

selenium

selenium-webdriver

webautomation