python中有一個(gè)第三方庫叫requests,提供了所有與http請(qǐng)求的相關(guān)函數(shù)
get請(qǐng)求
'''
get(url, param=None) -- 發(fā)送請(qǐng)求獲取服務(wù)器返回的響應(yīng)
url -- 請(qǐng)求地址掷豺。字符串
params -- 請(qǐng)求參數(shù)捞烟,字典
'''
import requests
方法1,試用post,get兩個(gè)
url = 'https://www.cnblogs.com/1fengchen1/p/9506985.html'
params = {'type':1,'page':2}
res = requests.get(url, params) #get自動(dòng)將url和param連接
print(res.status_code)
方法2,只試用于get
res = requests.get('https://www.cnblogs.com/1fengchen1/p/9506985.html?type=1&page=2')
獲取請(qǐng)求結(jié)果
1)響應(yīng)頭
print(res.headers)
2)響應(yīng)體(數(shù)據(jù))
a,獲取二進(jìn)制對(duì)應(yīng)的原數(shù)據(jù)(數(shù)據(jù)本身是圖片当船,視頻等二進(jìn)制數(shù)據(jù))
content = res.content
print(type(content))
b.獲取字符串類型的數(shù)據(jù)
text = res.text
print(type(text))
c.獲取json數(shù)據(jù)(json轉(zhuǎn)換成python對(duì)應(yīng)的數(shù)據(jù))
json1 = res.json()
print(type(json1))
print(json1)
線程
'''
每個(gè)線程中默認(rèn)都有一條線程题画,這個(gè)線程叫主線程,其他線程叫子線程
threading模塊中的Tread的對(duì)象就是線程對(duì)象德频,當(dāng)程序中需要子線程就創(chuàng)建Tread的對(duì)象
'''
import threading
from _datetime import datetime
import time
def downloads(film_name):
print('開始下載%s:%s'%(film_name, datetime.now()))
print(threading.current_thread())
time.sleep(5)
print('%s下載結(jié)束:%s'%(film_name, datetime.now()))
if _ _ name _ _ == '_ _ main _ _':
# downloads('西游')
# downloads('東游')
# downloads('北游')
#1.創(chuàng)建線程對(duì)象
'''
t1 = Tread(target=None, args=()) -- 創(chuàng)建并且返回一個(gè)子線程對(duì)象
target - 函數(shù)類型(function),在啟動(dòng)線程的時(shí)候這個(gè)函數(shù)會(huì)在子線程中執(zhí)行
args - 元組苍息,元組中的元素就是target對(duì)應(yīng)的函數(shù)在子線程中調(diào)用的時(shí)候傳的實(shí)參
'''
t1 = threading.Thread(target=downloads, args=('東游',))
t2 = threading.Thread(target=downloads, args=('西游',))
t3 = threading.Thread(target=downloads, args=('北游',))
# print(threading.current_thread())
#啟動(dòng)線程
'''
線程對(duì)象.start() -- 讓線程去執(zhí)行線程中的任務(wù)
target(*args)
'''
t1.start()
t2.start()
t3.start()
程序結(jié)束
'''
線程中的任務(wù)執(zhí)行完成線程就結(jié)束,程序出現(xiàn)異常結(jié)束的是線程,進(jìn)程不會(huì)結(jié)束档叔,進(jìn)程中的所有線程都結(jié)束桌粉,進(jìn)程才結(jié)束
'''
from threading import *
from datetime import datetime
import time
1.聲明一個(gè)類繼承Thread
2.實(shí)現(xiàn)類中的run方法,這個(gè)方法中的代碼就是需要在子線程中執(zhí)行的代碼
需要子線程的時(shí)候就創(chuàng)建自己聲明的類的對(duì)象衙四,并且不需要任何參數(shù)
class DownloadThread(Thread):
def init(self, file_name):
super().init()
self.file_name = file_name
def run(self) -> None:
print('開始下載%s:%s'%(self.file_name, datetime.now()))
print(current_thread())
time.sleep(5)
print('%s下載結(jié)束:%s'%(self.file_name, datetime.now()))
if name == 'main':
t1 = DownloadThread('東游')
t2 = DownloadThread('西游')
t1.start()
t2.start()
join
from threading import *
from datetime import datetime
from time import *
from random import randint
def download(film_name):
print('開始下載%s:%s'%(film_name, datetime.now()))
sleep(randint(3, 7))
print('%s結(jié)束下載:%s'%(film_name, datetime.now()))
if _ _ name _ _ == '_ _ main _ _':
1.join的用法
'''
線程對(duì)象.join() - 當(dāng)前線程對(duì)象任務(wù)執(zhí)行完成后才能去執(zhí)行后面的代碼
'''
t1 = Thread(target=download, args=('東游',))
t2 = Thread(target=download, args=('西游',))
t3 = Thread(target=download, args=('北游',))
t1.start()
t2.start()
t3.start()
t1.join()
t2.join()
t3.join()
print('下載完成')