How to use python multithreading to crawl weather website pictures and save them

This article mainly introduces how to use python multithreading to crawl weather website pictures and save, has a certain reference value, interested friends can refer to, I hope you can learn a lot after reading this article, the following let the editor take you to understand it.

1.1 topic

Specify a website to crawl all the images in the site, such as China Meteorological Network (www.weather.com.cn), using single-threaded and multithreaded crawls, respectively. (limit the number of crawled pictures to the last 3 digits of the student number)

Output information: output the downloaded Url information in the console, store the downloaded image in the images sub-file, and give a screenshot.

1.2 ideas

1.2.1 send request

Construct request header

Import requests,reimport urllibheaders = {'Connection':' keep-alive', 'Cache-Control':' max-age=0', 'Upgrade-Insecure-Requests':' 1, 'User-Agent':' Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.61 Safari/537.36', 'Accept':' text/html,application/xhtml+xml,application/xml Qcalendar 0.9 zh-CN,zh;q=0.9', zh-CN,zh;q=0.9', Avie url = "http://www.weather.com.cn/"request = urllib.request.Request (url, headers=headers)

Send a request

Request = urllib.request.Request (url, headers=headers) r = urllib.request.urlopen (request) 1.2.2 parsing web pages

The page is parsed, and enter is replaced to facilitate regular matching of images later.

Html = r.read () .decode () .replace

1.2.3 get the node

Using regular matching, get all the a tags first, and then crawl all the pictures under the a tags

UrlList = re.findall ('