Question

我想创建一个程序来加载json文件，读取该文件，然后添加一个反对列表。

import json

newo = {
    "balance": "1234",
    "time": "forever"
}

with open("json.json", "r") as f:
    data = json.load(f)

with open("json.json", "w") as f:
    json.dump(newo, f)

这是我一直在使用的python文件。

{ 
    "cointiply": [
        {
            "balance" : "242537",
            "time": "28.05.2019"
        },
        {
            "balance": "246362",
            "time": "29.05.2019"
        }
    ]
}

那是json文件。

我现在希望将newo列表“ cointiply”插入json列表中。

有什么想法可以做到吗？因为现在“ newo”列表正在删除json文件中的所有内容，然后才插入，就像文件将为空一样。

Answer 1

使用list.append

例如：

import json

newo = {
    "balance": "1234",
    "time": "forever"
}

with open("json.json", "r") as f:
    data = json.load(f)

data["cointiply"].append(newo)  #Append newo

with open("json.json", "w") as f:
    json.dump(data, f)

Answer 2

您可以尝试：

>>> demo = {
...     "cointiply": [
...         {
...             "balance" : "242537",
...             "time": "28.05.2019"
...         },
...         {
...             "balance": "246362",
...             "time": "29.05.2019"
...         }
...     ]
... }
>>> newo = {
...     "balance": "1234",
...     "time": "forever"
... }
>>> demo["cointiply"].append(newo)
>>> demo
{'cointiply': [{'balance': '242537', 'time': '28.05.2019'}, {'balance': '246362', 'time': '29.05.2019'}, {'balance': '1234', 'time': 'forever'}]}

Answer 3

您可以使用一个临时文件，向其中写入新数据，然后替换两个文件，而不必两次打开同一文件。关于列表-您需要使用append才能将新数据添加到cointiply元素中：

from os import remove
from shutil import move
from tempfile import mkstemp

newo = {
    "balance": "1234",
    "time": "forever"
}


fh, abs_path = mkstemp()
file_path = "json.json"
with open(fh, "w") as newf, open(file_path, "r") as oldf:
    data = json.load(oldf)
    data["cointiply"].append(newo)
    json.dump(data, newf)
    # Remove original file
    remove(file_path)
    # Move new file
    move(abs_path, file_path)

写入json中的特定对象。蟒蛇

3 个答案: