Python的履带 - AttributeError的：履带式实例没有属性 'URL'

Question

我努力学习Python中的类：

#!/usr/bin/env python 
# *-* coding: utf-8 *-* 

import urllib2 
from BeautifulSoup import BeautifulSoup as bs 

class Crawler: 

    def visit(self, url): 
     self.request = urllib2.Request(self.url) 
     self.response = urllib2.urlopen(self.request) 
     return self.response.read() 

if __name__ == "__main__": 
    x = Crawler() 
    print x.visit("http://google.com/") 

当我尝试启动正在错误：

sigo@sarch ~/sources $ python test.py 
Traceback (most recent call last): 
    File "test.py", line 16, in <module> 
    print x.visit("http://google.com/") 
    File "test.py", line 10, in visit 
    self.request = urllib2.Request(self.url) 
AttributeError: Crawler instance has no attribute 'url' 

我究竟做错了什么？

Answer 1

你在说self.url这是指Crawler类的url属性，它不存在。您只需要使用url，因为这是您的visit()函数参数中变量的名称。