Python NoneType 对象不可迭代
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NoneType object is not iterable
提问by Brandon
I am getting a 'NoneType' object is not iterable TypeError in the code below. The code below is ment to use pyautogui to scroll through 10 images in the digits folder (named 0 through 9, named with the # in the image) and when ever it finds one, report the value of x along with the number it found. The dictionary is then sorted by x values to read the number found in the image.
我在下面的代码中得到一个 'NoneType' 对象不是可迭代的 TypeError。下面的代码是使用 pyautogui 滚动数字文件夹中的 10 个图像（命名为 0 到 9，以图像中的 # 命名），并且当它找到一个时，报告 x 的值以及它找到的数字。然后字典按 x 值排序以读取图像中找到的数字。
Question:I am still learning Python and this TypeError has me stomped, how can I correct this?
问题：我仍在学习 Python 并且这个 TypeError 使我跺脚，我该如何纠正？
#! python3
import sys
import pyautogui
# locate Power
found = dict()
for digit in range(10):
positions = pyautogui.locateOnScreen('digits/{}.png'.format(digit),
region=(888, 920, 150, 40), grayscale=True)
for x, _, _, _ in positions:
found[x] = str(digit)
cols = sorted(found)
value = ''.join(found[col] for col in cols)
print(value)
Traceback of the error:
错误追溯：
Traceback (most recent call last):
File "C:\Users\test\python3.6\HC\power.py", line 10, in <module>
for x, _, _, _ in positions:
TypeError: 'NoneType' object is not iterable
回答by cur4so
You need to add check for Noneprior iteration through your positions
您需要None通过您的positions
#! python3
import sys
import pyautogui
# locate Power
found = dict()
for digit in range(10):
positions = pyautogui.locateOnScreen('digits/{}.png'.format(digit), region=(888, 920, 150, 40), grayscale=True)
if positions is not None:
for x, _, _, _ in positions:
found[x] = str(digit)
cols = sorted(found)
value = ''.join(found[col] for col in cols)
print(value)
