需要帮助弄清楚如何循环索引

Question

我正在从事一个围绕抓取大量数据的项目。我现在正在编写一个相当长的脚本，但是运行我的 for 循环遇到了问题。

我正在尝试从第 9 行中抓取信息 table。我试图设置一个 for 循环，以便它从每一行中抓取相同的信息。为了访问第一行，我将 table 拆分为一个列表。第一行从第三个索引开始。

这是我的代码：

当我运行它时，我得到一个 "AttributeError" 在行 "Aa" 上。错误显示，“'NoneType' 对象没有属性 'text'”

当我将该行代码单独输入控制台时，并没有发生这种情况，我得到了所需的文本。当我取出 for 循环时，我能够抓取第一个 indaplaybox。

from urllib.request import urlopen as uReq
from bs4 import BeautifulSoup as soup

my_url ='Myurl/=' + page

uClient = uReq(my_url)
page_html = uClient.read()
uClient.close()

page_soup = soup(page_html, "html.parser")
boxes = page_soup.findAll("table",{"class":"TableTable tableBody"})
box = boxes[0]
playboxes = box.find_all('tr')
indaplaybox = playboxes[3]

filename = "QBS.csv"
f = open(filename, "a")

headers= "Aa, Ab, Ac, Ad\n"
f.write(headers)

for indaplaybox in playboxes:

    Aa = indaplaybox.find('td', attrs = {'style' : 'font-weight: bold;'}).text

    c = indaplaybox.find('td', attrs = {'class' : 'tablePlayName'})
    cl = c.text.split() 
    Ab = cl[0] + " " + cl[1]
    Ac = cl[2]
    Ad = indaplaybox.div.a.text



    print("Aa:" + Aa)
    print("Ab:" + Ab)
    print("Ac:" + Ac)
    print("Ad:" + Ad)


    with open (filename, "a") as myfile:
        myfile.write(Aa + "," + Ab + "," + Ac.replace(",", "|") + "," + Ad + "\n")
f.close()

我想遍历播放框索引 3-11。

我不太熟悉索引，所以尝试做类似的事情：

p = [str(i) for i in range (3,12)] 
indaplaybox = playboxes[p]

for indaplaybox in playboxes:

    rest of code

但这行不通，因为对于大多数人来说可能显而易见的是列表索引必须是整数。

我真的需要一些帮助来思考如何顺利地获得这个 for 循环运行ning。谢谢！

Answer 1

p = [str(i) for i in range (3,12)] 
for i in p:
    indaplaybox = playboxes[i]
    ...
    rest of the code

Answer 2

你可以这样做：

方法一：

# p has all the values from playboxes at these indexes
p = [playboxes[i] for i in range(3,12)]

# now simple loop
for indaplaybox in p:
    ......

方法二：

for indaplaybox in playboxes[3:12]:
    ....

需要帮助弄清楚如何循环索引

Need help figuring out how to loop through indice

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web-scraping

indices