使用python3解析json

Question

新手python程序员在这里，我有以下json响应：

[
  {
    "type": "Incursion",
    "state": "mobilizing",
    "influence": 1,
    "has_boss": true,
    "faction_id": 500019,
    "constellation_id": 20000739,
    "staging_solar_system_id": 30005054,
    "infested_solar_systems": [
      30005050,
      30005051,
      30005052,
      30005053,
      30005054,
      30005055
    ]
  },
  {
    "type": "Incursion",
    "state": "established",
    "influence": 0,
    "has_boss": false,
    "faction_id": 500019,
    "constellation_id": 20000035,
    "staging_solar_system_id": 30000248,
    "infested_solar_systems": [
      30000244,
      30000245,
      30000246,
      30000247,
      30000248,
      30000249,
      30000250,
      30000251,
      30000252,
      30000253
    ]
  },
  {
    "type": "Incursion",
    "state": "mobilizing",
    "influence": 0,
    "has_boss": false,
    "faction_id": 500019,
    "constellation_id": 20000161,
    "staging_solar_system_id": 30001101,
    "infested_solar_systems": [
      30001097,
      30001098,
      30001099,
      30001100,
      30001101,
      30001102
    ]
  },
  {
    "type": "Incursion",
    "state": "established",
    "influence": 0,
    "has_boss": false,
    "faction_id": 500019,
    "constellation_id": 20000647,
    "staging_solar_system_id": 30004434,
    "infested_solar_systems": [
      30004425,
      30004426,
      30004427,
      30004428,
      30004429,
      30004430,
      30004431,
      30004432,
      30004433,
      30004434,
      30004435
    ]
  },
  {
    "type": "Incursion",
    "state": "established",
    "influence": 0.061500001698732376,
    "has_boss": false,
    "faction_id": 500019,
    "constellation_id": 20000570,
    "staging_solar_system_id": 30003910,
    "infested_solar_systems": [
      30003904,
      30003906,
      30003908,
      30003909,
      30003910,
      30003903
    ]
  }
]

原始代码是用来解析XML响应的。

下面是有问题的代码：

incursion_constellations = []

if (online):
    inc = urllib2.urlopen('https://esi.tech.ccp.is/latest/incursions/')
else:
    inc = file(r'incursions.json', 'r')

jinc = json.load(inc)

for j in jinc['items']:
    incursion_constellations.append(str(j['constellation']['id_str']))


for s in all_stations:
    cur.execute("SELECT constellationID FROM mapSolarSystems WHERE solarSystemID = " + str(s['ssid']))
    res = cur.fetchone()
    cid = str(res[0])
    s['incursion'] = cid in incursion_constellations

我有一个很难理解的地方是:对于jinc‘’items‘中的j

我得到了这个错误：

Traceback (most recent call last):
  File "./stations.py", line 201, in <module>
    for j in jinc['items']:
TypeError: list indices must be integers, not str

谁能帮助我理解如何将其转换为能够解析json响应、检索constellation_id并将其附加到列表中？

提前谢谢。

Answer 1

将原始循环更改为：

for j in jinc:
    incursion_constellations.append(str(j['constellation_id']))

但是您需要确保json中的constellation_id与之前['constellation']['id_str']下的id相同。

Answer 2

从响应的开头和结尾看，这个json响应似乎是list，而不是dict，正如您的错误所暗示的那样。

如果它是一个列表，那么您应该使用整数作为索引，而不是像在dict中那样使用str。因此，您的代码应该类似于

jinc[0]['constellation_id']

(我看不出“星座”部分是从哪里来的)

在和中的任何内容都在列表中，并且应该使用整数索引。{和}中的值在dict中，应该使用str索引。

要遍历它，只需使用range和len即可。

类似的问题已经在here上得到了回答。