为什么要用协程，python在执行并发任务时有：
多线程用锁，很容易造成数据不稳定,无法使用发挥多核CPU的能力
多进程耗资源
-
Python通过yield提供了对协程的基本支持，但是不完全。而第三方的gevent为Python提供了比较完善的协程支持。
- 安装gevent
- 安装： pip install greenlet
#-*- coding: utf-8 -*-
import urllib.request
# url = "http://r.qzone.qq.com/cgi-bin/user/cgi_personal_card?uin=284772894"
url = "http://gc.ditu.aliyun.com/geocoding?a="+urllib.request.quote("苏州市")
HEADER = {'Accept':'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8','User-Agent':'Mozilla/5.0 (Windows NT 6.1; rv:29.0) Gecko/20100101 Firefox/29.0'}
# 自定义请求的方法,get post
def f(url):
import urllib
import urllib.request
data=urllib.request.urlopen(url).read()
z_data=data.decode('UTF-8')
print(z_data)
# 我自己封装了gevent 的方法,重载了run
from gevent import Greenlet
class MyGreenlet(Greenlet):
def __init__(self, func):
Greenlet.__init__(self)
self.func = func
def _run(self):
# gevent.sleep(self.n)
self.func
count = 3
green_let = []
for i in range(0, count):
green_let.append(MyGreenlet(f(url)))
for j in range(0, count):
green_let[j].start()
for k in range(0, count):
green_let[k].join()
- 运行结果
D:\app\Python34\python.exe D:/app/dgm/field_study.py
{"lon":120.58531,"level":2,"address":"","cityName":"","alevel":4,"lat":31.29888}
{"lon":120.58531,"level":2,"address":"","cityName":"","alevel":4,"lat":31.29888}
{"lon":120.58531,"level":2,"address":"","cityName":"","alevel":4,"lat":31.29888}
