與來自 python/selenium 的 javascript 可滾動容器交互

Question

我正在嘗試使用 Selenium/Python 從http://factfinder.census.gov自動下載數據集。 我是 Javascript 的新手，如果這是一個容易解決的問題，我深表歉意。 我現在正在處理代碼的開頭部分，它應該：

1. 去這里
2. 單擊“主題”按鈕
3. 單擊“主題”並加載新頁面后，單擊“數據集”
4. 選擇我需要的數據集，最好是通過索引（子）表。

我被困在第 3 步。這是一個屏幕截圖； 似乎我想訪問帶有 ID“scrollable_container_topics”的 div，然后遍歷或索引以獲取其子節點（在這種情況下，我想要最后一個子節點）。 我曾嘗試使用 script_execute 然后通過 id 和類名定位元素，但到目前為止沒有任何效果。 我將不勝感激任何指點。

這是我的代碼：

import os
import re
import time
from selenium import webdriver
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions
from selenium.webdriver.support.wait import WebDriverWait
from selenium.webdriver.support.select import Select


# A list of all the variables we want to extract; corresponds to "Topics" field on site
topics = ["B03003", "B05001"]

# A list of all the states we want to extract data for (currently, strings; is there a numeric code?)
states = ["New Jersey", "Georgia"]

# A vector of all the years we want to extract data for [lower, upper) *Note* this != range of years covered by data
years = range(2009, 2010)

# Define the class
class CensusSearch:

    # Initialize and set attributes of the query
    def __init__(self, topic, state, year):

        """
        :type topic: str
        :type state: str
        :type year: int
        """
        self.topic = topic
        self.state = state
        self.year = year


    def setUp(self):

       # self.driver = webdriver.Chrome("C:/Python34/Scripts/chromedriver.exe")
        self.driver = webdriver.Firefox()

    def extractData(self):
        driver = self.driver
        driver.set_page_load_timeout(1000000000000)
        driver.implicitly_wait(100)

        # Navigate to site; this url = after you have already chosen "Advanced Search"
        driver.get("http://factfinder.census.gov/faces/nav/jsf/pages/searchresults.xhtml?refresh=t")
        driver.implicitly_wait(10)

        # FIlter by dataset (want the ACS 1, 3, and 5-year estimates)

        driver.execute_script("document.getElementsByClassName('leftnav_btn')[0].click()") # click the "Topics" button
        driver.implicitly_wait(20) 

        # This is where I am stuck; I've tried the following: 
        getData = driver.find_element_by_id("ygtvlabelel172")
        getData.click()
        driver.implicitly_wait(10)


        # Filter geographically: select all counties in the United States and Puerto Rico
        # Click "Geographies" button
        driver.execute_script("document.getElementsByClassName('leftnav_btn')[1].click()")
        driver.implicitly_wait(10)

        drop_down = driver.find_element_by_class_name("popular_summarylevel")
        select_box = Select(drop_down)
        select_box.select_by_value("050")

    # Once "Geography" is clicked, select "County - 050" from the drop-down menu; then select "All US + Puerto Rico"
    drop_down_counties = driver.find_element_by_id("geoAssistList")
    select_box_counties = Select(drop_down_counties)
    select_box_counties.select_by_index(1)

    # Click the "ADD TO YOUR SELECTIONS" button
    driver.execute_script("document.getElementsByClassName('button-g')[0].click()")
    driver.implicitly_wait(10)

    def tearDown(self):
        self.driver.quit()

    def main(self):
        #print(getattr(self))
        print(self.state)
        print(self.topic)
        print(self.year)
        self.setUp()
        self.extractData()
        self.tearDown()


for a in topics:
    for b in states:
        for c in years:
            query = CensusSearch(a, b, c)
            query.main()

print("done")

Answer 1

要解決的幾件事：

• 您不必使用document.getElement..方法 - selenium 有自己的方法來定位頁面上的元素
• 無需操作隱式等待（另外，請確保您了解調用implicitly_wait()不會像time.sleep() -在這種情況下，您不會立即獲得時間延遲）或頁面加載超時-只需使用在頁面上執行操作之前顯式等待

這是一個工作代碼，單擊“主題”，然后單擊“數據集”：

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


driver = webdriver.Firefox()
driver.get("http://factfinder.census.gov/faces/nav/jsf/pages/searchresults.xhtml?refresh=t")

wait = WebDriverWait(driver, 10)
actions = ActionChains(driver)

# click "Topics"
topics = wait.until(EC.element_to_be_clickable((By.CSS_SELECTOR, "a#topic-overlay-btn")))
driver.execute_script("arguments[0].click();", topics)

# click "Dataset"
dataset = wait.until(EC.element_to_be_clickable((By.CSS_SELECTOR, "span[title=Dataset]")))
dataset.click()