Question

UPDATE： if语句没有被执行，这很奇怪，因为我在Django之外测试了脚本，只在Python中工作。

我知道这个问题在这里被多次询问过，但我找不到能帮我弄清楚错误的答案。这是我得到的错误：

local variable 'what_i_need' referenced before assignment

这是我在VIEWS中的代码：

from django.http import HttpResponse
from django.shortcuts import render

from urllib2 import urlopen
from bs4 import BeautifulSoup

def test(request):
    someURL = "https://www.example.com/"
    urlOpen = urlopen(someURL).read()
    soup = BeautifulSoup(urlOpen)
    for x in soup.findAll('span'):
        if 'something' in str(x):
            info = x.get_text()
            info = info.split()
            info = info[0]
            info = info.replace(".", '')
            what_i_need = info
    return HttpResponse(what_i_need)

我做错了什么？

Answer 1

问题是if声明。如果它从未执行过，what_i_need永远不会被初始化，因此错误（因为你不能将一个整数变量传递给HttpResponse）。只需将其初始化为None等（根据您的需要）

def test(request):
    someURL = "https://www.example.com/"
    urlOpen = urlopen(someURL).read()
    soup = BeautifulSoup(urlOpen)
    what_i_need = None            # Initialized here
    for x in soup.findAll('span'):
        if 'something' in str(x):
            info = x.get_text()
            info = info.split()
            info = info[0]
            info = info.replace(".", '')
            what_i_need = info
    return HttpResponse(what_i_need)

在分配之前引用的变量

1 个答案: