Question

我想更改嵌套键的值，但出现此错误

key['score'] = new_score # come back to this
 TypeError: 'str' object does not support item assignment

这是我的代码：

def add_score(self, obj):
        for child in reversed(self.root.screen_two.ids.streak_zone.children):
            name = child.text

            with open("streak.json", "r+") as read_file:
                data = json.load(read_file)

            for key in data.keys():
                if key == name:
                    score = data.get(key, {}).get('score')
                    new_score = score + 1
                    key['score'] = new_score # come back to this

这是我的json文件的样子：

{"one": {"action": "one", 
        "delay": 1557963534.4314187, 
        "seconds": 60, 
        "score": 0, 
        "delta": 1557963474.4314187}, 
 "two": {"action": "two", 
         "delay": 1557963664.037102, 
         "seconds": 120, 
         "score": 0, 
         "delta": 1557963544.037102}, 
 "three":{"action": "three", 
          "delay": 1557963792.4683638, 
          "seconds": 180, 
          "score": 0, 
          "delta": 1557963612.4683638}
}

如何更改json文件中的score值？

Answer 1

您应该能够直接更新字典元素。

替换以下内容

for key in data.keys():
    if key == name:
        score = data.get(key, {}).get('score')
        new_score = score + 1
        key['score'] = new_score # come back to this

使用

data[name]['score'] += 1

代码应该是

def add_score(self, obj):
        for child in reversed(self.root.screen_two.ids.streak_zone.children):
            name = child.text

            with open("streak.json", "r+") as read_file:
                data = json.load(read_file)

            data[name]['score'] += 1

Answer 2

在for循环中，您要遍历键数组（在您的情况下为['one','two','three']。

尝试以下代码。希望这会有所帮助！

for key,value in data.items():
    if key == name:
        score = value['score']       
        new_score = score + 1
        value['score'] = new_score

或者在下面使用一种衬纸，而不是在循环中使用

data[name]['score']+=1  #name='one'

在文件内编辑

with open('streak.json', 'r+') as f:
    data = json.load(f)
    data[name]['score']+=1 
    f.seek(0)
    json.dump(data, f, indent=4)
    f.truncate()

Answer 3

这应该有效

with open("a.json", "r+") as read_file:
    data = json.load(read_file)
    data[name]['score'] += 1 # update score

with open("a.json", "w") as json_file: #write it back to the file
    json.dump(data, json_file)

如何更改json文件中嵌套键的值？

3 个答案: