我可以使用 Firefox.get_screenshot_as_file('2.png') 对整个页面进行屏幕截图，但是当我使用passage.screenshot('1.png') 对网页元素进行屏幕截图时，它总是会引发此异常：
selenium.common.exceptions.WebDriverException: Message: Unrecognized command: GET /session/284283fa-53fc-4b33-b329-e6e888dbdcb0/screenshot/{35834cf1-c9c7-4129-99b1-24f30c6b56e6}
您之所以会遇到此异常，是因为如果没有一些第三方库或您自己的代码来处理此问题，您就无法仅截取 selenium 中的一个元素的屏幕截图。看这个 stackoverflow 帖子
它使用一个名为 PIL 的库来完成此操作：
from selenium import webdriver
from PIL import Image
fox = webdriver.Firefox()
fox.get('https://stackoverflow.com/')
# now that we have the preliminary stuff out of the way time to get that image :D
element = fox.find_element_by_id('hlogo') # find part of the page you want image of
location = element.location
size = element.size
fox.save_screenshot('screenshot.png') # saves screenshot of entire page
fox.quit()
im = Image.open('screenshot.png') # uses PIL library to open image in memory
left = location['x']
top = location['y']
right = location['x'] + size['width']
bottom = location['y'] + size['height']
im = im.crop((left, top, right, bottom)) # defines crop points
im.save('screenshot.png') # saves new cropped image