python - 获取网页时出现“NoneType 对象不可调用”错误

Question

我对python很陌生，我写了这段代码

def geturl(url):
    url = urllib.quote(url,'/:')
    log( __name__ ,"Getting url:[%s]" % url)
    try:
        req = urllib2.Request(url)
        response = urllib2.urlopen(req)
        content    = response.read()
        return_url = response.geturl()
        response.close()
    except Exception, e:
        log( __name__ ,"Failed to get url because %s" % str(e))
        content    = None
        return_url = None
    return(content, return_url)

def myFunc():
    searchurl="http://www.google.com"
    socket.setdefaulttimeout(3)
    content, response_url = geturl(searchurl)
    if content is None:
        log( __name__ , "Content is None!!")
    content = content.replace("string1", "string2")

当我运行它时，我收到此错误：NoneType 对象不可调用。我不明白为什么......我了解到 NoneType 是 None 的类型，但我检查“content”变量是否为 None 并且不是。谢谢你的帮助

Answer 1

您没有给出错误的行，但是我怀疑以下内容是错误的：

if content is None:
    log( __name__ , "Content is None!!")
content = content.replace("string1", "string2")

当contentis Indeed时None，会发出一条日志，但函数会继续执行，直到调用replace引发异常。