selenium中的對文本進行全選，復制，粘貼，剪切和刪除的操作

# 鍵盤全選操作
from selenium.webdriver.common.keys import Keys
driver.find_element_by_css_selector('#key-demo').send_keys(Keys.CONTROL,'a')
time.sleep(2)

# 鍵盤的復制操作
driver.find_element_by_css_selector('#key-demo').send_keys(Keys.CONTROL,'c')
time.sleep(2)

#鍵盤的剪切操作
driver.find_element_by_css_selector('#key-demo').send_keys(Keys.CONTROL,'x')
time.sleep(2)

#鍵盤的粘貼操作
driver.find_element_by_css_selector('#key-demo').send_keys(Keys.CONTROL,'v')
time.sleep(2)

#鍵盤的刪除操作
driver.find_element_by_css_selector('#key-demo').send_keys(Keys.CONTROL,'a')
driver.find_element_by_css_selector('#key-demo').send_keys(Keys.BACKSPACE)
time.sleep(2)