Question

我将从网络抓取工具中解析的内容写入CSV文件时遇到问题。

csvfile = open('names.csv', 'a+')
fieldnames = ['news_url','news_title','news_author','date_pub','date_up','news_desc']
writer = csv.DictWriter(csvfile, fieldnames=fieldnames)    
writer.writeheader()
data_list = {
    'news_url': news_url,
    'news_title': news_title,
    'news_author': news_author,
    'date_pub': date_pub,
    'date_up': date_up,
    'news_desc': news_desc,
}
if '' not in data_list.values():
    writer.writerow(data_list)

我得到如下文件的格式

https://s3-us-west-2.amazonaws.com/my-contents/names.csv

Answer 1

您尚未包含数据的外观。我假设你有一个数据值列表。

从您拥有的代码中，data_list只是一行。因此，它应该使用writerow()的单个调用来编写，不需要迭代您创建的data_list字典：

import csv

fieldnames = ['news_url', 'news_title', 'news_author', 'date_pub', 'date_up', 'news_desc']

with open('names.csv', 'w', newline='') as f_output:
    csv_output = csv.DictWriter(f_output, fieldnames=fieldnames)
    csv_output.writeheader()

    data = [
        ['url1', 'title1', 'author1', '1/1/2018', '2/1/2018', 'blah1'],
        ['url2', 'title2', 'author2', '1/1/2018', '2/1/2018', 'blah2'],
        ['url3', 'title3', 'author3', '1/1/2018', '2/1/2018', 'blah3'],
        ['url4', 'title4', 'author4', '1/1/2018', '2/1/2018', 'blah4']]

    for news_url, news_title, news_author, date_pub, date_up, news_desc in data:
        data_list = {
            'news_url': news_url,
            'news_title': news_title,
            'news_author': news_author,
            'date_pub': date_pub,
            'date_up': date_up,
            'news_desc': news_desc}

        csv_output.writerow(data_list)

哪个会创建names.csv，其中包含：

news_url,news_title,news_author,date_pub,date_up,news_desc
url1,title1,author1,1/1/2018,2/1/2018,blah1
url2,title2,author2,1/1/2018,2/1/2018,blah2
url3,title3,author3,1/1/2018,2/1/2018,blah3
url4,title4,author4,1/1/2018,2/1/2018,blah4

如果您的数据与上面的data非常相似，那么使用DictWriter有点过分，因为您的数据已经是正确顺序和大小的元素列表。如果是这种情况，以下方法将更容易：

import csv

fieldnames = ['news_url', 'news_title', 'news_author', 'date_pub', 'date_up', 'news_desc']

with open('names.csv', 'w', newline='') as f_output:
    csv_output = csv.writer(f_output)
    csv_output.writerow(fieldnames)

    data = [
        ['url1', 'title1', 'author1', '1/1/2018', '2/1/2018', 'blah1'],
        ['url2', 'title2', 'author2', '1/1/2018', '2/1/2018', 'blah2'],
        ['url3', 'title3', 'author3', '1/1/2018', '2/1/2018', 'blah3'],
        ['url4', 'title4', 'author4', '1/1/2018', '2/1/2018', 'blah4']]

    csv_output.writerows(data)

这会产生相同的输出。他们都假设你使用的是Python 3.x.

将值从字典写入csv行时出现问题

1 个答案: