这是我的代码，我给出了rec项目(这是列表中的第一个项目(，并将其放置在选择器语句中。其意图是，当运行自动chrome驱动程序时，它必须单击具有该名称的元素。
for rec in recipients:
driver.find_element_by_css_selector("span[title='" + recipient + "']").click()
driver.find_element_by_xpath('// *[ @ id = "main"] / footer / div[1] / div[2] / div /
div[2]').send_keys(message)
driver.find_element_by_xpath('//*[@id="main"]/footer/div[1]/div[3]').click()
但是，我得到了无效的选择器异常
Traceback (most recent call last):
File "/Users/archanaradhakrishnan/PycharmProjects/Gmail/whatsapp.py", line 52, in <module>
driver.find_element_by_css_selector('//span[contains(@title,' + '"' + recipient + '"' + ')]')
File "/Users/archanaradhakrishnan/venv/lib/python3.7/site-packages/selenium/webdriver/remote/webdriver.py", line 598, in find_element_by_css_selector
return self.find_element(by=By.CSS_SELECTOR, value=css_selector)
File "/Users/archanaradhakrishnan/venv/lib/python3.7/site-packages/selenium/webdriver/remote/webdriver.py", line 978, in find_element
'value': value})['value']
File "/Users/archanaradhakrishnan/venv/lib/python3.7/site-packages/selenium/webdriver/remote/webdriver.py", line 321, in execute
self.error_handler.check_response(response)
File "/Users/archanaradhakrishnan/venv/lib/python3.7/site-packages/selenium/webdriver/remote/errorhandler.py", line 242, in check_response
raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.InvalidSelectorException: Message: invalid selector: An invalid or illegal selector was specified
(Session info: chrome=83.0.4103.116)
你错了：
File "/Users/archanaradhakrishnan/PycharmProjects/Gmail/whatsapp.py", line 52, in <module>
driver.find_element_by_css_selector('//span[contains(@title,' + '"' + recipient + '"' + ')]')
您通过rec in recipients进行了一个for循环，但您调用了recipient。