迭代通過JSON [Python的]

Question

我讀的蟒蛇以下JSON文件：

{ 
    "name": "Property", 
    "base": "PersistedModel", 
    "idInjection": true, 
    "options": { 
    "validateUpsert": true 
    }, 
    "properties": { 
    "uuid": { 
     "type": "string" 
    }, 
    "userID": { 
     "type": "number" 
    }, 
    "address": { 
     "type": "string" 
    }, 
    "price": { 
     "type": "number" 
    }, 
    "lastUpdated": { 
     "type": "string" 
    } 
    }, 
    "validations": [], 
    "relations": { 
    "rooms": { 
     "type": "hasMany", 
     "model": "Room", 
     "foreignKey": "id" 
    }, 
    "addedByUser": { 
     "type": "hasMany", 
     "model": "User_ESPC", 
     "foreignKey": "id" 
    } 
    }, 
    "acls": [], 
    "methods": {} 
} 

我想讀的properties並獲得屬性的名稱（如的「uuid」），併爲每個名稱我想讀取對象的類型。到目前爲止，我的代碼列出了所有類似的特性：

Property name: price 
Property name: userID 
Property name: uuid 
Property name: lastUpdated 
Property name: address 

，做這是該代碼：

import json 

#json_file='a.json' 
json_file='common/models/property.json' 
with open(json_file, 'r') as json_data: 
    data = json.load(json_data) 


propertyName = data["name"] 
properties = data["properties"] 

# print (properties) 

for property in properties: 
    print ('Property name: ' + property) 
    # propertyType = property["type"] 
    # print (propertyType) 

問題是，當我去掉底部的2線，應該得到的類型屬性對象我得到一個錯誤：

Property name: price 
Traceback (most recent call last): 
File "exportPropertyToAndroid.py", line 19, in <module> 
propertyType = property["type"] 
TypeError: string indices must be integers 

Answer 1

迭代字典會產生它的鍵。 properties是一本字典：

properties = data["properties"] 

，當你遍歷它：

for property in properties: 
    print ('Property name: ' + property) 
    # propertyType = property["type"] 
    # print (propertyType) 

property引用依次在每個關鍵。由於你的字典代表JSON數據，所以鍵是字符串，錯誤是非常明顯的。 property["type"]正嘗試從字符串"type"處獲取字符。

相反，你應該要麼使用鍵property從字典中獲取更多的價值：

for property in properties: 
    print ('Property name: ' + property) 
    propertyType = properties[property]["type"] 
    print(propertyType) 

或遍歷鍵和值：

for property, value in properties.items(): 
    print ('Property name: ' + property) 
    propertyType = value["type"] 
    print(propertyType)