BeautifulSoup / Python - 将 HTML 表转换为 CSV 并获取一列的 href

Question

我正在用这段代码抓取一个 HTML 表格：

import csv
import urllib2
from bs4 import BeautifulSoup

with open('listing.csv', 'wb') as f:
    writer = csv.writer(f)
    for i in range(39):
        url = "file:///C:/projects/HTML/Export.htm".format(i)
        u = urllib2.urlopen(url)
        try:
            html = u.read()
        finally:
            u.close()
        soup=BeautifulSoup(html)
        for tr in soup.find_all('tr')[2:]:
            tds = tr.find_all('td')
            row = [elem.text.encode('utf-8') for elem in tds]
            writer.writerow(row)

一切正常，但我正在尝试获取第 9 列的 Href URL。它目前给我的是 txt 值，但不是 URL。

另外，我的 HTML 中有两个表，无论如何要跳过第一个表并使用第二个表构建 csv 文件？

非常欢迎任何帮助，因为我是 Python 新手，并且在我正在自动执行每日转换的项目中需要此帮助。

非常感谢！

Answer 1

您应该在第 8 个td 标签内访问a 标签的href 属性：

import csv
import urllib2
from bs4 import BeautifulSoup

records = []
for index in range(39):
    url = get_url(index)  # where is the formatting in your example happening?
    response = urllib2.urlopen(url)
    try:
        html = response.read()
    except Exception:
        raise
    else:
        my_parse(html)
    finally:
        try:
            response.close()
        except (UnboundLocalError, NameError):
            raise UnboundLocalError

def my_parse(html):
    soup = BeautifulSoup(html)
    table2 = soup.find_all('table')[1]
    for tr in table2.find_all('tr')[2:]:
        tds = tr.find_all('td')
        url = tds[8].a.get('href')
        records.append([elem.text.encode('utf-8') for elem in tds])
        # perhaps you want to update one of the elements of this last
        # record with the found url now?

# It's more efficient to write only once
with open('listing.csv', 'wb') as f:
    writer = csv.writer(f)
    writer.writerows(records)

我冒昧地根据索引定义了一个函数get_url，因为您的示例每次都会重新读取同一个文件，我猜您实际上并不想要。我将把实现留给你。此外，我还添加了一些更好的异常处理。

同时，我展示了如何从该网页的表格访问第二个表格。

Answer 2

完全能够使用以下代码使其工作：

import csv
import urllib2
from bs4 import BeautifulSoup

#Grab second table from HTML
def my_parse(html):
    soup = BeautifulSoup(html)
    table2 = soup.find_all('table')[1]
    for tr in table2.find_all('tr')[2:]:
        tds = tr.find_all('td')
        url = tds[8].a.get('href')
    tds[8].a.replaceWith(url)
        records.append([elem.text.encode('utf-8') for elem in tds])

records = []
#Read HTML file into memory
for index in range(39):
    url = "file:///C:/projects/HTML/Export.htm".format(index)
    response = urllib2.urlopen(url)
    try:
        html = response.read()
    except Exception:
        raise
    else:
        my_parse(html)
    finally:
        try:
            response.close()
        except (UnboundLocalError, NameError):
            raise UnboundLocalError

#Writing CSV file
with open('listing.csv', 'wb') as f:
    writer = csv.writer(f)
    writer.writerows(records)

非常感谢大家的帮助！！！！！！