Question

我有以下python脚本

from bs4 import BeautifulSoup
import requests

home_dict = []

for year in range(2005, 2021):
    if year == 2020:
        for month in range(1, 6):
            url = 'https://www.rebgv.org/market-watch/MLS-HPI-home-price-comparison.hpi.all.all.' + str(year) + '-' + str(month) + '-1.html';
            r = requests.get(url)
            soup = BeautifulSoup(r.text, 'html.parser')

            home_table = soup.find('div', class_="table-wrapper")
            for home in home_table.find_all('tbody'):
                rows = home.find_all('tr')
                for row in rows:
                    area = row.find('td').text;
                    benchmark = row.find_all('td')[1].text
                    priceIndex = row.find_all('td')[2].text
                    oneMonthChange = row.find_all('td')[3].text
                    sixMonthChange = row.find_all('td')[4].text
                    oneYearChange = row.find_all('td')[5].text
                    threeYearChange = row.find_all('td')[6].text
                    fiveYearChange = row.find_all('td')[7].text
                    propertyType = row.find_all('td')[8].text
                    year = year;
                    month = month;

                    home_obj = {
                        "Area": area,
                        "Benchmark": benchmark,
                        "Price Index": priceIndex,
                        "1 Month +/-": oneMonthChange,
                        "6 Month +/-": sixMonthChange,
                        "1 Year +/-": oneYearChange,
                        "3 Year +/-": threeYearChange,
                        "5 Year +/-": fiveYearChange,
                        "Property Type": propertyType,
                        "Report Month": month,
                        "Report Year": year
                    }
                    home_dict.append(home_obj)
    else:
        for month in range(1, 13):
            url = 'https://www.rebgv.org/market-watch/MLS-HPI-home-price-comparison.hpi.all.all.' + str(year) + '-' + str(month) + '-1.html';
            r = requests.get(url)
            soup = BeautifulSoup(r.text, 'html.parser')

            home_table = soup.find('div', class_="table-wrapper")
            for home in home_table.find_all('tbody'):
                rows = home.find_all('tr')
                for row in rows:
                    area = row.find('td').text;
                    benchmark = row.find_all('td')[1].text
                    priceIndex = row.find_all('td')[2].text
                    oneMonthChange = row.find_all('td')[3].text
                    sixMonthChange = row.find_all('td')[4].text
                    oneYearChange = row.find_all('td')[5].text
                    threeYearChange = row.find_all('td')[6].text
                    fiveYearChange = row.find_all('td')[7].text
                    propertyType = row.find_all('td')[8].text
                    year = year;
                    month = month;

                    home_obj = {
                        "Area": area,
                        "Benchmark": benchmark,
                        "Price Index": priceIndex,
                        "1 Month +/-": oneMonthChange,
                        "6 Month +/-": sixMonthChange,
                        "1 Year +/-": oneYearChange,
                        "3 Year +/-": threeYearChange,
                        "5 Year +/-": fiveYearChange,
                        "Property Type": propertyType,
                        "Report Month": month,
                        "Report Year": year
                    }
                    home_dict.append(home_obj)
        
                
print(home_dict)

此脚本是通过网络抓取网站。如果年份是2020年，那么只能从1月到5月。其他年份，则从一月到十二月。

您可以告诉我们，如果在if-else条件语句中重复脚本的主体，是否有更简单的方法编写此脚本，以使其看起来更整洁而不重复自身？

Answer 1

也许尝试使用try子句？

for year in range(2005, 2021):
    month in range(1, 13):
        try:
            <your code>
        except:
            continue

Answer 2

只需定义一个dict，将年作为键并将月范围作为值，

filter_ = {2020 : (1, 6)}

for year in range(2005, 2021):
    start, stop = filter_.get(year, (1,13))

    for month in range(start, stop):
        url = 'https://www.rebgv.org/market-watch/MLS-HPI-home-price-comparison.hpi.all.all.' + str(
            year) + '-' + str(month) + '-1.html'
        r = requests.get(url)
        ...

Answer 3

因为刮擦通常需要1到6个月。您可以先取消这些年份。然后如果年份不等于2020，则可以取消其余年份

用Python编写条件语句的更简洁方法

3 个答案: