无法在discord.py中的命令中打开和写入文件两次

Question

我想打开一个json文件，为了保护其中的安全，几秒钟后，我想再次删除它。我已经在dpy支持中问过。他们说，我无法在写入模式下打开文件。但是，无论如何我如何打开文件？或如何摆脱这种写入模式？

我尝试过：

@bot.command()
@commands.has_permissions(administrator=True)
async def knastmute(ctx, member: discord.Member = None, arg1= None, *, arg2=None):
    guild = bot.get_guild(597135532111167622)
    knastmute = get(guild.roles, id=696100186149224545)
    Knast = 686657535427739804

    guildemojisbtv = bot.get_guild(712671329123303504)
    Epositiv = get(guildemojisbtv.emojis, id=712679512873369610)
    Eerror = get(guildemojisbtv.emojis, id=713187214586282054)

    if member:
        if any(role.id == Knast for role in member.roles):
                    if arg1 == '1m':

                        with open(r'./knastmuteusers.json', 'r')as f:
                            users = json.load(f)
                        if not f"{member.id}" in users:
                            users[member.id] = f"{member}: {arg1}"
                            with open(r"./knastmuteusers.json", 'w') as f:
                                json.dump(users, f, indent=4)

                                await member.add_roles(knastmute)

                                await asyncio.sleep(5)

                                with open(r'./knastmuteusers.json', 'r')as f:
                                    users = json.load(f)
                                    del users[member.id]

                                    with open(r"./knastmuteusers.json", 'w') as f:
                                        json.dump(users, f, indent=4)

                                        await member.remove_roles(knastmute)

我收到此错误：

I get this error:
    ```Ignoring exception in command knastmute:
Traceback (most recent call last):
  File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\site-packages\discord\ext\commands\core.py", line 83, in wrapped
    ret = await coro(*args, **kwargs)
  File "F:\DiscordBot\PyCharm\blacktv.py", line 2327, in knastmute
    users = json.load(f)
  File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\json\__init__.py", line 296, in load
    parse_constant=parse_constant, object_pairs_hook=object_pairs_hook, **kw)
  File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\json\__init__.py", line 348, in loads
    return _default_decoder.decode(s)
  File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\json\decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\json\decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\site-packages\discord\ext\commands\bot.py", line 892, in invoke
    await ctx.command.invoke(ctx)
  File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\site-packages\discord\ext\commands\core.py", line 797, in invoke
    await injected(*ctx.args, **ctx.kwargs)
  File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\site-packages\discord\ext\commands\core.py", line 92, in wrapped
    raise CommandInvokeError(exc) from exc
discord.ext.commands.errors.CommandInvokeError: Command raised an exception: JSONDecodeError: Expecting value: line 1 column 1 (char 0)

Answer 1

发生的事情是您正在尝试打开文件，但仍在打开该文件。从上下文管理器中取消缩进会自动关闭文件。

错误本身表明文件格式不正确，很可能看起来像这样：

{

如果您未将有效格式的数据写入.json，则会发生这种情况。

---

这里是一个示例命令，它多次读取/写入文件：

import os # necessary if you wish to check the file exists

@bot.command()
async def cmd(ctx):
    if os.path.isfile("file.json"):
        with open("file.json", "r") as fp:
            data = json.load(fp) # loads the file contents into a dict with name data
        data["users"].append(ctx.author.id) # add author's id to a list with key 'users'
    else: # creating dict for json file if the file doesn't exist
        data = {
            "users": []
        }
        data["users"].append(ctx.author.id)

    # outside of if statement as we're writing to the file no matter what
    with open("file.json", "w+") as fp:
        json.dump(data, fp, sort_keys=True, indent=4) # kwargs are for formatting

    print(data) # you're still able to access the dict after closing the file
    await ctx.send("Successfully updated a file!")

---

参考：

• json.dump()
• json.dump()