如何從python中的嵌套數組中計算嵌套的json對象

Question

如何獲得所有運動中的對象總數？

目前，盡管下面所有嘗試挖掘節點的嘗試都失敗了，但我在下面的代碼片段中並未獲得成功。

import json

RESULTS = 'sample.json'
with open(RESULTS) as f:
    data = json.load(f)
    results = data
print(len(results[0]['result']['movements'])) #Expected: 3

sample.json

[
  {
    "result": {
      "TempId": "369477387",
      "movements": [
        {
          "date": "2018-05-03",
          "credit": 100.0,
          "shorttext": "My<br/>Expense "
        },
        {
          "date": "2018-05-03",
          "debit": 200.0,
          "shorttext": "My<br/>F\u00dcR"
        }
      ]
    }
  },
  {
    "result": {
      "TempId": "369477395",
      "movements": []
    }
  },
  {
    "result": {
      "TempId": "369477402",
      "movements": [
        {
          "date": "2018-05-07",
          "credit": 100.0,
          "shorttext": "My<br/>Expense "
        }
      ]
    }
  }
]

Answer 1

使用列表推導，您可以從樣本列表中找出每個元素的movements次數。

然后只需將sum方法應用於count列表即可找出總和。

count = sum([len(item['result']['movements']) for item in sample])

輸出量

>> count
3