Selenium - 检查元素是否存在，否则检查是否存在另一个元素（在python中）

Question

I'm writing a program that scrapes courses from my schools website and i'm trying to check what element is present after I click on the search button.

If 'id1' is present then that means the course is not available and the next course needs to be searched, else if 'id2' is present then that means the course is available so scrape it and search the next course.

This is what I have at the moment but it's not working. I've tired using webdriverwait with conditional statements but I couldn't get it to work either. So how can I solve this?

while(i < len(courseNumList)):
   self.clearAndSearch(courseNumList[i], coursePrefixList[i])

   if(len(self.driver.find_elements_by_id('id1')) > 0):
      i = i + 1
      continue
   self.scrapeAndModifySearch(courses, INDEX_NAME, TYPE_NAME)
      i = i + 1

scrapeAndModifySearch():

def scrapeAndModifySearch(self, courses, esindex, estypename):
   self.getCourses(courses, esindex, estypename)
   self.modifySearch()

getCourses():

def getCourses(self, courses, INDEX_N, TYPE_N):
   course = {}

   try:
      element_present = EC.presence_of_element_located((By.ID, 'id2'))
      WebDriverWait(self.driver, 30).until(element_present)
   except TimeoutException:
      print ("Loading took too much time!")

   classSectionsFound = self.driver.find_element_by_xpath('id2').text

Answer 1

Seems you've mixed up your locators. That last line should be:

   classSectionsFound = self.driver.find_element_by_id('id2').text

'id2' is not valid xpath (at least not for a HTML doc).