如何遍历 JSON 数组？ [关闭]

Question

我有这个带有多个根的 JSON 数组：

[
  {
  "issuer_ca_id": 16418,
  "issuer_name": "C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3",
  "name_value": "sub.test.com",
  "min_cert_id": 325717795,
  "min_entry_timestamp": "2018-02-08T16:47:39.089",
  "not_before": "2018-02-08T15:47:39"
  },
{
"issuer_ca_id":9324,
"issuer_name":"C=US, O=Amazon, OU=Server CA 1B, CN=Amazon",
"name_value":"marketplace.test.com",
"min_cert_id":921763659,
"min_entry_timestamp":"2018-11-05T19:36:18.593",
"not_before":"2018-10-31T00:00:00",
"not_after":"2019-11-30T12:00:00"
}
]

我想遍历它并在 Python 中打印 issuer_name 值。请问有什么解决办法吗？

Answer 1

使用json 包并加载json。假设它是内存中的字符串（而不是.json 文件）：

jsonstring = """
[
  {
  "issuer_ca_id": 16418,
  "issuer_name": "C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3",
  "name_value": "sub.test.com",
  "min_cert_id": 325717795,
  "min_entry_timestamp": "2018-02-08T16:47:39.089",
  "not_before": "2018-02-08T15:47:39"
  },
{
"issuer_ca_id":9324,
"issuer_name":"C=US, O=Amazon, OU=Server CA 1B, CN=Amazon",
"name_value":"marketplace.test.com",
"min_cert_id":921763659,
"min_entry_timestamp":"2018-11-05T19:36:18.593",
"not_before":"2018-10-31T00:00:00",
"not_after":"2019-11-30T12:00:00"
}
]"""

import json
j = json.loads(jsonstring)
[item["issuer_name"] for item in j]

给予：

["C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3",
 'C=US, O=Amazon, OU=Server CA 1B, CN=Amazon']

现在，这些在我看来不像是名称，但这是分配给 issuer_name 字段的名称，所以我认为这是您必须与数据所有者讨论的内容。

如果它是一个文件，你可以按照这个基本模式进行加载：

# something like this
with open("jsonfile.json", "rb") as fp:
    j = json.load(fp) 

在此处查看文档：https://docs.python.org/3.7/library/json.html