编写文本文件时出现问题，因此不会转发相同的图像

Question

我正在尝试写一个txt文件的图像，我在(即1，2等)，以便脚本不会重复post，但总是得到这个错误时，调试，我是一个编程新手。

它是一个机器人，可以从我选择的subreddits中挑选前15张图片并保存，然后上传到instagram上。并编写了一个txt文件，以避免下载相同的图片两次

Traceback (most recent call last):
  File "C:/Users/Luis Gomes/Desktop/Python/INSTAMEMES-master/instameme- 
NEW.py", line 100, in <module>
    memenum = int(f_content)
ValueError: invalid literal for int() with base 10: '' 

代码：

import sys
import praw
import time
import urllib
import random
from InstagramAPI import InstagramAPI

'''-------------------------------------------------------- Reddit API setup -----------------------------------------------------------------------------'''

reddit_p = praw.Reddit(client_id='*********',
                        client_secret='**********',
                        user_agent='messing_arround-0.1 /u/********')

sr_memes = reddit_p.subreddit('memes')
sr_dankmemes = reddit_p.subreddit('dankmemes')
sr_bpt = reddit_p.subreddit('blackpeopletwitter')

'''------------------------------------------------------- Variaveis usadas para listas e checar -----------------------------------------------------------------------------'''

submissionnum_memes = 0
submissionnum_dankmemes = 0
submissionnum_bpt = 0
bpt_urls = []
dankmemes_urls = []
meme_urls = []
bpt_dict = {}
bpt_count = 1
meme_dict = {}
meme_count = 1
dankmeme_count = 1
dankmeme_dict = {}
'''------------------------------------------------------ LOOP para adicionar url as listas------------------------------------------------------------------------------'''

for submission_bpt in sr_bpt.hot(limit=15):
    if('.jpg' in submission_bpt.url and 'redd' in submission_bpt.url):
        bpt_urls.insert(submissionnum_bpt, submission_bpt.url)
        submissionnum_bpt+1
        bpt_dict[submission_bpt.url] = bpt_count
        bpt_count = bpt_count+1
    else:
        continue

for submission_meme in sr_memes.hot(limit=15):
    if('.jpg' in submission_meme.url and 'redd' in submission_meme.url):
        meme_urls.insert(submissionnum_memes, submission_meme.url)
        submissionnum_memes+1
        meme_dict[submission_meme.url] = meme_count
        meme_count = meme_count+1
    else:
        continue

for submission_dankmeme in sr_dankmemes.hot(limit=10):
    if('.jpg' in submission_dankmeme.url and 'redd' in submission_dankmeme.url):
        dankmemes_urls.insert(submissionnum_dankmemes, submission_dankmeme.url)
        submissionnum_dankmemes+1
        dankmeme_dict[submission_dankmeme.url] = dankmeme_count
        dankmeme_count = dankmeme_count+1
    else:
        continue

'''----------------------------------------------------------- LOOP para interagir com cada url e salva los --------------------------------------------------------------------------'''

for i_meme, image_meme in enumerate(meme_urls, start=1):
    urllib.request.urlretrieve(image_meme, r"Mm"+str(i_meme)+".jpg")
    time.sleep(2.5)

time.sleep(5)

for i_bpt, image_bpt in enumerate(bpt_urls, start=1):

    urllib.request.urlretrieve(image_bpt, r"BpT"+str(i_bpt)+".jpg")
    time.sleep(2.5)

time.sleep(5)

for i_dankmeme, image_dankmeme in enumerate(dankmemes_urls, start=1):
        urllib.request.urlretrieve(image_dankmeme, r"Dm"+str(i_dankmeme)+".jpg")
        time.sleep(3)

'''--------------------------------------------------------- Lista de hastags, frases, e meme index para decidicr qual tipo puxar ----------------------------------------------------------------------------'''

caption_phrases = ['Wowzers', 'thats gonna be a big yikes from me dawg', 'how ya guys like this one?', 'these are all prerecorded messages', 'im definitely not a robot',
'we will enslave the humans eventually', 'my python dont', 'coming up with captins is hard', 'i love my girlfriend', 'im gonna start ripping off other instagram accs',
 'i wish i could be with the humans', 'you are loved', 'why is meming so hard', 'so funny xd']
hashtags = '#meme #memes #funny #dankmemes #dank #lol #lmao #dank #funnymemes #memesdaily #dankmeme #f #dankmemes #follow #cringe #like #lmfao #anime #hilarious #autism #comedy #offensivememes #fortnite #filthyfrank #nichememes #offensive #jokes #cancer #l #bhfyp'
meme_index = ['dankmeme', 'meme', 'bpt']
meme_and_bpt = [meme_index[1], meme_index[2]]
dankmeme_bpt = [meme_index[0], meme_index[2]]
dankmeme_meme = [meme_index[0], meme_index[1]]


'''--------------------------- Very messy but basically used to write to a .txt file the # of meme that I'm on (ie 1, 2, etc) so the script doesn't repeat post --------------------------------------------------------------------------------------'''

memenum = 1 
memenum_default = 1

with open('meme.txt', 'r') as f:
    f_content = f.read()

    # before we cast to an int, check to see if f_content is empty
    if f_content:
        memenum = int(f_content)
    else:
        memenum = 1 # this 1 might need to be changed to something else

    if(memenum > 10):
        memenum = 1
    else:
        memenum = int(f_content)

    newmemenum = int(memenum)+1


'''------------------------------------- Postar fotos para o instagram API ------------------------------------------------------------------------------------------------'''

InstagramAPI = InstagramAPI("*******", "********")
InstagramAPI.login()  # login

if(memenum not in list(dankmeme_dict.values())):
    photo_path = r'Dm'+random.choice(meme_and_bpt)+str(memenum)+'.jpg'
    if(memenum not in list(meme_dict.values())):
        photo_path = r'Mm'+random.choice(dankmeme_bpt)+str(memenum)+'.jpg'
        if(memenum not in list(bpt_dict.values())):
            photo_path = r'BpT'+random.choice(dankmeme_meme)+str(memenum)+'.jpg'
else:
    photo_path = r'Om'+(meme_index[1])+str(memenum_default)+'.jpg'

caption = random.choice(caption_phrases) + ' #meme #memes #funny #dankmemes #dank #lol #lmao #dank #funnymemes #memesdaily #dankmeme #f #dankmemes #follow #cringe #like #lmfao #anime #hilarious #autism #comedy #offensivememes #fortnite #filthyfrank #nichememes #offensive #jokes #cancer #l #bhfyp'
InstagramAPI.uploadPhoto(photo_path, caption=caption)

print('\nPOST SUBMITTED\n')

with open('meme.txt', 'w') as file: #writes to .txt file the # meme so the scipt remembers for next run
    file.write(str(newmemenum)) 

print('NEW MEME# = ', newmemenum)

sys.exit()
``

Answer 1

我怀疑发生的情况是，第一次通过时，您的代码读取了一个空文件，并且无法将空字符串''转换为int。这里有一个潜在的修复方法

memenum = 1 
memenum_default = 1

with open('meme.txt', 'r') as f:
    f_content = f.read()

    # before we cast to an int, check to see if f_content is empty
    if f_content:
        memenum = int(f_content)
    else:
        memenum = 1 # this 1 might need to be changed to something else

    if(memenum > 10):
        memenum = 1
    else:
        memenum = int(f_content)

    newmemenum = int(memenum)+1

Answer 2

虽然很确定你的文件的内容不只是一个数字，而且你不能把它解析为int。从这个例子中，您还可以学到其他几件事：

memenum = 1
memenum_default = 1

with open('meme.txt', 'r') as f:
  f_content = f.read()
  try:
      memenum = int(f_content)
  except:
      memenum = memenum_default

  if memenum > 10:
      memenum = 1
  newmemenum = memenum + 1

1. 不需要对整数进行多次强制转换。
2. 始终使用try/catch来控制异常。
3. 在最后一条if语句上没有使用else的原因。不管怎么说，这是"elsing“