day10_ Multithreading 3

# Multi-threaded to write six Web sites into a file (parallel)

Import requests,time,threading

def write_html (url,name):

r = Requests.get (URL)

With open (name, ' W ', encoding = ' UTF8 ') as F:

F.write (R.text)

urls = [' www.nnzhp.cn ', ' www.besttest.cn ', ' www.imdsx.cn ', ' sb.nnzhp.cn ',' bbs.besttest.cn ', ' Video.besttest.cn '] #六个网站URL

Lis = [] # Store each thread

Start_time = Time.time ()

For URL in URLs: # Loop each URL

new_file = '/http ' + URL

file_name = URL + '. html '

t = Threading. Thread (target = Write_html,args = (new_url,file_name)) # instantiates a thread

Lis.append (t)

T.start () # Start a thread

# Start six threads, let them run, the main thread waits for them, join is the main thread waiting for each sub-thread to finish executing

For obj in Lis:

Obj.join () # Join must be placed outside of the six threads that are started

End_time = Time.time ()

Print (' program runs in total ', end_time-start_time)

The main thread waits for the child thread to crawl all the pages and then the main thread to send the message

day10_ Multithreading 3