写入csv文件python的第二列

我有一个Python程序，在从CSV文件（只有一列）中读取餐厅名称后，它可以获得谷歌对餐厅的评级。名称在一列中（第一列）。它获取每个餐厅的评级并将其添加到列表中。现在我需要创建第二列，并将该列表传递到第二列。这是我的CSV文件（它没有标题，即列的名称）

代码如下：

import requests
from bs4 import BeautifulSoup
import csv


def main():
    global rate
    ratings = []
    res = []
    with open('CSV restaurants example.csv', newline='', encoding='utf-8') as f:
        reader = csv.reader(f)

        for row1 in reader:
            for row in row1:
                res.append(row)
    for restaurant in res:
        try:
            re = requests.get('https://www.google.com/search?q=' + restaurant)
        except requests.exceptions.ChunkedEncodingError:
            re = requests.get('https://www.google.com/search?q=' + restaurant)

        soup = BeautifulSoup(re.content, 'html.parser')

        rating = soup.select_one('.oqSTJd')
        try:
            rate = rating.text
            ratings.append(rate)
        except AttributeError:
            print("google search is asking for captcha, use a proxy or change your wifi network")
            exit()

        print('\nThe rating for ' + restaurant + ' is ' + str(rate) + ' out of 5 ' + '\n')


if __name__ == '__main__':
    main()

---

关于如何将该列表附加到第二列有何建议？

试试这个，它会创建一个带有第二列评级的熊猫对象，您可以将其转换为csv：

import requests
import pandas as pd
from bs4 import BeautifulSoup
import csv


def main():
    global rate
    ratings = []
    res = []
    with open('CSV restaurants example.csv', newline='', encoding='utf-8') as f:
        reader = csv.reader(f)

        for row1 in reader:
            for row in row1:
                res.append(row)
    for restaurant in res:
        try:
            re = requests.get('https://www.google.com/search?q=' + restaurant)
        except requests.exceptions.ChunkedEncodingError:
            re = requests.get('https://www.google.com/search?q=' + restaurant)

        soup = BeautifulSoup(re.content, 'html.parser')

        rating = soup.select_one('.oqSTJd')
        try:
            rate = rating.text
            ratings.append(rate)
        except AttributeError:
            print("google search is asking for captcha, use a proxy or change your wifi network")
            exit()

        print('\nThe rating for ' + restaurant + ' is ' + str(rate) + ' out of 5 ' + '\n')
    df2 = pd.read_csv('CSV restaurants example.csv', header=None, names=['Restaurants']) 
    df2['ratings'] = ratings
    print(df2)
    print("")
    print(df2.to_csv())
    return df2

if __name__ == '__main__':
    df2 = main()

您可以重写回csv，而不使用如下标题：

df2.set_index("Restaurants").to_csv(header=False)

# 'Barrafina london,4.5\npalomar london,4.6\nfateema london,4.8\nfive guys london,4.2\n10 greek street london,4.5\nedition hotel london,4.6\n'

---

只需创建一个

csv.writer

来赞美您的

csv.reader

。如果要将输出保存为新文件，我建议永远不要覆盖原始数据，即使只是向其中添加数据

我要说的是，您可能需要小心分隔符，因为位置和餐厅字段似乎合并了，在我看来，这就像是格式错误的csv中的两列

在这里，您可以在相同的for循环中解决它：

import requests
from bs4 import BeautifulSoup
import csv


def main():
    # global rate
    # ratings = []
    # res = []
    with open('CSV restaurants example.csv', newline='', encoding='utf-8') as infd, \
             open('restaurants_with_ratings.csv') as outfd:
        reader = csv.reader(infd)

        # create a csv writer, these are defaults, but I'm showing that 
        # you can choose formatting
        writer = csv.writer(outfd, delimiter=',', quotechar='"')

        # if there's only one column, the comma works here.
        for restaurant, in reader:
            # res.append(row)

            try:
                re = requests.get('https://www.google.com/search?q=' + restaurant)
            except requests.exceptions.ChunkedEncodingError:
                re = requests.get('https://www.google.com/search?q=' + restaurant)

            soup = BeautifulSoup(re.content, 'html.parser')

            rating = soup.select_one('.oqSTJd')
            try:
                rate = rating.text
                writer.writerow([restauant, rate])  # add a column
                # ratings.append(rate)
            except AttributeError:
                print("google search is asking for captcha, use a proxy or change your wifi network")
                exit()

            print('\nThe rating for ' + restaurant + ' is ' + str(rate) + ' out of 5 ' + '\n')


if __name__ == '__main__':
    main()

import requests
from bs4 import BeautifulSoup
import csv


def main():
    # global rate
    # ratings = []
    # res = []
    with open('CSV restaurants example.csv', newline='', encoding='utf-8') as infd, \
             open('restaurants_with_ratings.csv') as outfd:
        reader = csv.reader(infd)

        # create a csv writer, these are defaults, but I'm showing that 
        # you can choose formatting
        writer = csv.writer(outfd, delimiter=',', quotechar='"')

        # if there's only one column, the comma works here.
        for restaurant, in reader:
            # res.append(row)

            try:
                re = requests.get('https://www.google.com/search?q=' + restaurant)
            except requests.exceptions.ChunkedEncodingError:
                re = requests.get('https://www.google.com/search?q=' + restaurant)

            soup = BeautifulSoup(re.content, 'html.parser')

            rating = soup.select_one('.oqSTJd')
            try:
                rate = rating.text
                writer.writerow([restauant, rate])  # add a column
                # ratings.append(rate)
            except AttributeError:
                print("google search is asking for captcha, use a proxy or change your wifi network")
                exit()

            print('\nThe rating for ' + restaurant + ' is ' + str(rate) + ' out of 5 ' + '\n')


if __name__ == '__main__':
    main()