python - CSV 导入循环重复次数

Question

对于 Python 世界来说相当陌生。我编写了以下脚本来转换 csv 文件并覆盖现有的 JSON 文件，准备上传到 Firebase。问题是，脚本读取每一行 4 次，这很奇怪。我的代码如下，很高兴知道我哪里出错了。

import csv
import json
from collections import OrderedDict

fieldnames = ("Code", "Currency", "Rate", "Last Updated")
entries = []

with open('rates.csv', 'r') as csvfile:
    reader = csv.DictReader(csvfile, fieldnames)
    for row in reader:
        entry = OrderedDict()
        for field in fieldnames:
            entry[field] = row[field]
            entries.append(entry)

output = {
    "rates": entries
    }

with open('rates2.json', 'w') as jsonfile:
    json.dump(output, jsonfile, indent=2, ensure_ascii=False)
    jsonfile.write('\n')

CSV 示例 CSV IMAGE

示例输出

{
  "rates": [
    {
      "Code": "AED ",
      "Currency": " UAE Dirham",
      "Rate": "4.2499",
      "Last Updated": "18/02/2020 10:13"
    },
    {
      "Code": "AED ",
      "Currency": " UAE Dirham",
      "Rate": "4.2499",
      "Last Updated": "18/02/2020 10:13"
    },
    {
      "Code": "AED ",
      "Currency": " UAE Dirham",
      "Rate": "4.2499",
      "Last Updated": "18/02/2020 10:13"
    },
    {
      "Code": "AED ",
      "Currency": " UAE Dirham",
      "Rate": "4.2499",
      "Last Updated": "18/02/2020 10:13"
    },
    {
      "Code": "AUD ",
      "Currency": " Australian Dollar",
      "Rate": "1.8299",
      "Last Updated": "18/02/2020 10:13"
    },
    {
      "Code": "AUD ",
      "Currency": " Australian Dollar",
      "Rate": "1.8299",
      "Last Updated": "18/02/2020 10:13"
    },
    {
      "Code": "AUD ",
      "Currency": " Australian Dollar",
      "Rate": "1.8299",
      "Last Updated": "18/02/2020 10:13"
    },
    {
      "Code": "AUD ",
      "Currency": " Australian Dollar",
      "Rate": "1.8299",
      "Last Updated": "18/02/2020 10:13"
    }
  ]
}

Answer 1

只需取消缩进entries.append(...):

with open('rates.csv', 'r') as csvfile:
    reader = csv.DictReader(csvfile, fieldnames)
    for row in reader:
        entry = OrderedDict()
        for field in fieldnames:
            entry[field] = row[field]
        entries.append(entry)

否则，您将为每个字段附加一个新行，而实际上您只想每行执行一次，而不是每个字段执行一次。