【发布时间】:2026-02-23 00:45:02
【问题描述】:
我下面的代码没有按照我想要的方式工作,我尝试对其进行一些评论以使其更容易。
基本上我希望它最多尝试3次访问网站,如果成功则退出循环并继续,如果失败3次则退出函数。
import random
import urllib2
import httplib
import urllib
import mechanize
def test():
## For three attempts...
for i in range(0, 3):
## While in the three attempts...
while True:
## Try...
try:
print "trying"
## Proxy list
proxy_list = {"No Proxy": "None"}
## Randomly chosen proxy
proxy_number = random.choice(proxy_list.keys())
## URL to post to in order to get data.
post_url = ""
browser = mechanize.Browser()
browser.set_handle_robots(False)
browser.addheaders = [('User-agent', 'Firefox')]
parameters = {""}
data = urllib.urlencode(parameters)
## If proxy_number = No Proxy then...
if proxy_number == "No Proxy":
## Do not setup proxy details
proxy_details = None
## If proxy_number is a real proxy then...
else:
## Get the proxy details
proxy_details = proxy_list[proxy_number]
## Setup the proxy
browser.set_proxies({"http": proxy_number})
## Contact the webpage
trans_array = browser.open(post_url).read().decode('UTF-8')
print trans_array
## If successfully exit loop
break
## On exceptions
except:
## If unsuccessful continue and retry
continue
## End the current loop
break
## If it was unsuccessful after three attempts return false
return
print trans_array
test()
谁能解释我做错了什么?
编辑:对于 falsetru
def test():
for i in range(3):
try:
...
break
except:
counter = counter + 1
print counter
continue
if counter == 3:
return False
提前致谢 - 海福克斯
【问题讨论】:
-
在我看来,因为你继续异常,如果每次都发生异常,while循环将无限执行
-
你的 while 循环将永远为真,for 循环永远不会超过范围 1
标签: python python-2.7 random proxy mechanize