如何以 Pythonic 的方式检测 CSV 文件中的缺失字段? [英] How do I detect missing fields in a CSV file in a Pythonic way?

问题描述

我正在尝试使用 Python 的 csv 模块(特别是 DictReader 类)解析 CSV 文件.有没有 Pythonic 的方法来检测空字段或缺失字段并抛出错误?

I'm trying to parse a CSV file using Python's csv module (specifically, the DictReader class). Is there a Pythonic way to detect empty or missing fields and throw an error?

这是一个使用以下标题的示例文件:NAME、LABEL、VALUE

Here's a sample file using the following headers: NAME, LABEL, VALUE

foo,bar,baz
yes,no
x,y,z

解析时，我希望第二行抛出错误，因为它缺少 VALUE 字段.

When parsing, I'd like the second line to throw an error since it's missing the VALUE field.

这是一个代码片段，它显示了我是如何处理这个问题的(忽略硬编码的字符串......它们只是为了简洁起见):

Here's a code snippet which shows how I'm approaching this (disregard the hard-coded strings...they're only present for brevity):

import csv

HEADERS = ["name", "label", "value" ]
fileH = open('configFile')
reader = csv.DictReader(fileH, HEADERS)

for row in reader:
    if row["name"] is None or row["name"] == "":
        # raise Error
    if row["label"] is None or row["label"] == "":
        # raise Error
    ...
fileH.close()

是否有一种更简洁的方法来检查 CSV 文件中的字段，而无需使用一堆 if 语句?如果我需要添加更多字段，我还需要更多条件，我希望尽可能避免.

Is there a cleaner way of checking for fields in the CSV file w/out having a bunch of if statements? If I need to add more fields, I'll also need more conditionals, which I would like to avoid if possible.

推荐答案

if any(row[key] in (None, "") for key in row):
    # raise error

编辑:更好:

if any(val in (None, "") for val in row.itervalues()):
    # raise error

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