自从 seleniun 官网被限制访问后，且后面一段时间都用得较少，已经有一段时间未持续关注它的动态。时过几年，发现它有一些非常好的新特性。下文都以 python 作为开发语言。

with 关键字

from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support.expected_conditions import presence_of_element_located

#This example requires Selenium WebDriver 3.13 or newer
with webdriver.Firefox() as driver:
    wait = WebDriverWait(driver, 10)
    driver.get("https://google.com/ncr")
    driver.find_element(By.NAME, "q").send_keys("cheese" + Keys.RETURN)
    first_result = wait.until(presence_of_element_located((By.CSS_SELECTOR, "h3>div")))
    print(first_result.get_attribute("textContent"))

指定元素，前后左右相对定位

• above
• below
• toLeftOf
• toRightOf
• near

#from selenium.webdriver.support.relative_locator import with_tag_name
passwordField = driver.find_element(By.ID, "password")
emailAddressField = driver.find_element(with_tag_name("input").above(passwordField))

#from selenium.webdriver.support.relative_locator import with_tag_name
emailAddressField = driver.find_element(By.ID, "email")
passwordField = driver.find_element(with_tag_name("input").below(emailAddressField))

#from selenium.webdriver.support.relative_locator import with_tag_name
submitButton = driver.find_element(By.ID, "submit")
cancelButton = driver.find_element(with_tag_name("button").
                                   to_left_of(submitButton))

#from selenium.webdriver.support.relative_locator import with_tag_name
cancelButton = driver.find_element(By.ID, "cancel")
submitButton = driver.find_element(with_tag_name("button").
                                   to_right_of(cancelButton))

near()

Returns the WebElement, which is at most 50px away from the specified element.

#from selenium.webdriver.support.relative_locator import with_tag_name
emailAddressLabel = driver.find_element(By.ID, "lbl-email")    
emailAddressField = driver.find_element(with_tag_name("input").
                                       near(emailAddressLabel))

页面加载策略（Page loading strategy）

normal

This will make Selenium WebDriver to wait for the entire page is loaded. When set to normal, Selenium WebDriver waits until the load event fire is returned.

By default normal is set to browser if none is provided.

from selenium import webdriver
from selenium.webdriver.chrome.options import Options
options = Options()
options.page_load_strategy = 'normal'
driver = webdriver.Chrome(options=options)
# Navigate to url
driver.get("http://www.google.com")
driver.quit()

eager

This will make Selenium WebDriver to wait until the initial HTML document has been completely loaded and parsed, and discards loading of stylesheets, images and subframes.

When set to eager, Selenium WebDriver waits until DOMContentLoaded event fire is returned.

none

When set to none Selenium WebDriver only waits until the initial page is downloaded.