如何修复此python-硒try-except块？

Question

我有一个python类来处理一些基本的硒元素。 方法之一是包装器，用于检查页面上是否存在某些元素：

from selenium.common.exceptions import TimeoutException, NoSuchElementException

...

def check_element(self, by, element):
    try:
        self.driver.find_element(by, element)  
        return True
    except TimeoutException, NoSuchElementException:
        return False

我用这样的方法调用此方法：

self._base.check_element((By.XPATH, '//*[@id="kernel_indicator_icon"]))

但是在运行代码时，出现意外错误：

  ...
  File "/Users/adietz/Projects/Jenkins/selenium-tests/selenium_tests/tools/basicsuite.py", line 277, in check_element
    self.driver.find_element(by, element)
  File "/Users/adietz/Projects/Jenkins/venv_selenium/lib/python2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 858, in find_element
    'value': value})['value']
  File "/Users/adietz/Projects/Jenkins/venv_selenium/lib/python2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 311, in execute
    self.error_handler.check_response(response)
  File "/Users/adietz/Projects/Jenkins/venv_selenium/lib/python2.7/site-packages/selenium/webdriver/remote/errorhandler.py", line 237, in check_response
    raise exception_class(message, screen, stacktrace)
NoSuchElementException: Message: Unable to locate element: //*[@id="kernel_indicator_icon" and @title="Kernel Idle"]

为什么上面的try-except块没有捕获此异常？

Answer 1

从文档直接

def check_element(self, by, element):
    try:
        self.driver.find_element(by, element)  
        return True
    except (TimeoutException, NoSuchElementException) as e:
        return False