在 python 循环中调节

Question

import time
import pyautogui


location = pyautogui.locateOnScreen('ok.png')

pyautogui.click(location)

如何将以下语句编写为代码？

如果在屏幕上找不到图像，请保持运行 location直到找到图像。

否则代码将立即终止。

我试过了：

While location == None : #Or location == False
    pyautogui.click(location)

Answer 1

尝试像这样使用 while：

while location is not None:
    pyautogui.click(location)

Answer 2

根据 Pyautogui documentation:

If the image can’t be found on the screen, locateOnScreen() raises ImageNotFoundException

这意味着您必须处理错误消息才能保留程序运行，以防图像不存在。尝试使用异常处理：

import pyautogui

while True:
    # Try to do this
    try:
        location = pyautogui.locateOnScreen('ok.png')
        # Location found with no errors: break the while loop and proceed
        break
    # If an error has occurred (image not found), keep waiting
    except:
        pass

pyautogui.click(location)

注意： 这会生成无限循环，直到在屏幕上找到图像。要打破此循环并停止脚本执行，请在 Shell.

上使用 CTRL+C

或者，您可以设置等待图像的最长时间：

import time
import pyautogui

max_wait = 30 # Seconds
end = time.time() + max_wait

while time.time() <= end:
    # Try to do this
    try:
        location = pyautogui.locateOnScreen('ok.png')
        # Location found with no errors: break the while loop and proceed
        break
    # If an error has occurred (image not found), keep waiting
    except:
        pass    
    
pyautogui.click(location)

在 python 循环中调节

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pyautogui