动作链

### 动作链

```python
# 模拟鼠标点住，拖动的效果，实现滑块认证
# 两种形式
# 	-形式一：
#         actions=ActionChains(bro) #拿到动作链对象
#         actions.drag_and_drop(sourse,target) #把动作放到动作链中，准备串行执行
#         actions.perform()
#     -方式二：
#     	ActionChains(bro).click_and_hold(sourse).perform()
#     	distance=target.location['x']-sourse.location['x']
#         track=0
#         while track < distance:
#             ActionChains(bro).move_by_offset(xoffset=2,yoffset=0).perform()
#             track+=2


from selenium import webdriver
from selenium.webdriver import ActionChains
from selenium.webdriver.support.wait import WebDriverWait  # 等待页面加载某些元素

import time
from selenium.webdriver.common.by import By

browser = webdriver.Chrome()
browser.get('http://www.runoob.com/try/try.php?filename=jqueryui-api-droppable')
browser.implicitly_wait(10)
browser.maximize_window()

try:
    browser.switch_to.frame('iframeResult')
    sourse = browser.find_element(By.ID, 'draggable')
    target = browser.find_element(By.ID, 'droppable')
    # 方式一：基于同一个动作链串行执行
    # action = ActionChains(browser)
    # action.drag_and_drop(sourse, target)
    # action.perform()
    # 方式二：不同的动作链，每次移动的位移都不同
    ActionChains(browser).click_and_hold(sourse).perform()# 鼠标点中源 标签 不松开
    distance=target.location['x']-sourse.location['x']
    track=0
    while track<distance:
        ActionChains(browser).move_by_offset(xoffset=2,yoffset=0).perform()
        track+=2
    ActionChains(browser).release().perform()



    time.sleep(3)
finally:
    browser.close()