Question

下面的功能可以正常工作，除非它扫描页面并发现标签“ fullview-news-outer”不存在。这将产生错误“列表索引超出范围” 。我该怎么做才能确保标记“ fullview-news-outer”存在，如果不退出，则相应地设置表变量。

def get_news2(ticker):
    """
    Returns a list of sets containing news headline and url
    """
    page_parsed, _ = http_request_get(url=STOCK_URL, payload={'t': ticker}, parse=True)
    table = page_parsed.cssselect('table[class="fullview-news-outer"]')[0]
    ...
    return (df)

Answer 1

正如巴尔玛所说的

table = page_parsed.cssselect('table[class="fullview-news-outer"]')
 if len(table) > 0:
      tbl_first = table[0]

Answer 2

您无需尝试捕获即可解决问题

page_parsed, _ = http_request_get(url=STOCK_URL, payload={'t': ticker}, parse=True) 
selected = page_parsed.cssselect('table[class="fullview-news-outer"]')
if selected:
    table = selected[0]

需要尝试捕获块

2 个答案: