爬取武汉近七日天气

元旦假期朋友圈被大雪刷爆了，遗憾的是我出去旅行了没有看到武汉的第一场大雪~

堆雪人.jpg
夜晚大雪.jpg
查看了武汉近7日的天气，希望还能遇上一场大雪，能愉快的堆雪人、打雪仗~
http://www.weather.com.cn/weather/101200101.shtml
虽然用手机查询天气很方便，但写代码更有成就感。我用python中的Beautiful Soup库爬取信息，代码如下：
首先导入需要的库

import requests
import csv
from bs4 import BeautifulSoup
from requests.exceptions import  RequestException  #捕获异常

获取需要的数据

需求数据.png

def get_content(url , data = None):
    try:
        header = {
            'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.81 Safari/537.36'
        }
        rep = requests.get(url, headers=header)
        rep.encoding = 'utf-8'
        if rep.status_code==200:
            return rep.text
    except RequestException:
        return '请求异常'

def get_data(html_text):
    final = []
    bs = BeautifulSoup(html_text, "html.parser")  
    body = bs.body 
    data = body.find('div', {'id': '40d'}) 
    ul = data.find('ul')  
    li = ul.find_all('li') 


    for day in li: 
        temp = []
        date = day.find('h1').string 
        temp.append(date)  
        inf = day.find_all('p')  
        temp.append(inf[0].string,)  
        if inf[1].find('span') is None:
            temperature_highest = None # 天气预报可能没有当天的最高气温，需要加个判断语句,来输出最低气温
        else:
            temperature_highest = inf[1].find('span').string 
            temperature_highest = temperature_highest.replace('℃', '')  # 到了晚上网站会变，最高温度后面也有个℃
        temperature_lowest = inf[1].find('i').string 
        temperature_lowest = temperature_lowest.replace('℃', '')  # 最低温度后面有个℃，去掉这个符号
        temp.append(temperature_highest)   
        temp.append(temperature_lowest)  
        final.append(temp)   

    return final

写入文件

def write_data(data, name):
    file_name = name
    with open(file_name, 'a', errors='ignore', newline='') as f:
            f_csv = csv.writer(f)
            f_csv.writerows(data)

if __name__ == '__main__':
    url ='http://www.weather.com.cn/weather/101200101.shtml'
    html = get_content(url)
    result = get_data(html)
    write_data(result, '2.weather.csv')

运行后输出的表格如下：

武汉近7日天气.png