如何用python和beautifulsoup解析html表并写入csv
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How to parse html table with python and beautifulsoup and write to csv
提问by user2140323
I try to parse html page and fetch values for currencies and write to csv. I have following code:
我尝试解析 html 页面并获取货币值并写入 csv。我有以下代码：
#!/usr/bin/env python
import urllib2
from BeautifulSoup import BeautifulSoup
contenturl = "http://www.bank.gov.ua/control/en/curmetal/detail/currency?period=daily"
soup = BeautifulSoup(urllib2.urlopen(contenturl).read())
table = soup.find('div', attrs={'class': 'content'})
rows = table.findAll('tr')
for tr in rows:
cols = tr.findAll('td')
for td in cols:
text = td.find(text=True) + ';'
print text,
print
The problem is, that I do not know, how to retrieve only values for currency. I tried some regexp like '^[0-9]{3}' - start with 3 digits but it doesn't work.
问题是，我不知道如何仅检索货币值。我尝试了一些像 '^[0-9]{3}' 这样的正则表达式 - 以 3 位数字开头，但它不起作用。
采纳答案by Martijn Pieters
You'd be much better off picking out specific cells in the table. The tdcells with the cell_cclass contain data you are interested in, and the last one is always the currency exchange rate:
您最好选择表格中的特定单元格。td具有cell_c该类的单元格包含您感兴趣的数据，最后一个始终是货币汇率：
rows = table.findAll('tr')
for tr in rows:
cols = tr.findAll('td')
if 'cell_c' in cols[0]['class']:
# currency row
digital_code, letter_code, units, name, rate = [c.text for c in cols]
print digital_code, letter_code, units, name, rate
With the data in separate variables, you can now turn the text to decimal numbers, store them in a database, whatever.
使用单独变量中的数据，您现在可以将文本转换为十进制数字，将它们存储在数据库中，等等。
