比閱讀線更好的方法？

Question

使用Python 2.5，我正在讀取HTML文件，以獲取三種不同的信息。 我能夠找到信息的方式是找到與正則表達式 *的匹配項，然后從匹配行開始向下計數特定的行數，以獲取我正在尋找的實際信息。 問題是我必須重新打開該站點3次（對於我正在查找的每條信息，均應打開一次）。 我認為這效率低下，希望只查找一次打開站點的所有三件事。 有誰有更好的方法或建議？

* 我將學習更好的方法，例如BeautifulSoup，但就目前而言，我需要快速修復

碼：

def scrubdividata(ticker):
try:
    f = urllib2.urlopen('http://dividata.com/stock/%s'%(ticker))
    lines = f.readlines()
    for i in range(0,len(lines)):
        line = lines[i]
        if "Annual Dividend:" in line:
            s = str(lines[i+1])
            start = '>\$'
            end = '</td>'
            AnnualDiv = re.search('%s(.*)%s' % (start, end), s).group(1)
    f = urllib2.urlopen('http://dividata.com/stock/%s'%(ticker))
    lines = f.readlines()
    for i in range(0,len(lines)):
        line = lines[i]
        if "Last Dividend:" in line:
            s = str(lines[i+1])
            start = '>\$'
            end = '</td>'
            LastDiv = re.search('%s(.*)%s' % (start, end), s).group(1)
    f = urllib2.urlopen('http://dividata.com/stock/%s'%(ticker))
    lines = f.readlines()
    for i in range(0,len(lines)):
        line = lines[i]
        if "Last Ex-Dividend Date:" in line:
            s = str(lines[i+1])
            start = '>'
            end = '</td>'
            LastExDivDate = re.search('%s(.*)%s' % (start, end), s).group(1)
    divlist.append((ticker,LastDiv,AnnualDiv,LastExDivDate))
except:
    if ticker not in errorlist:
        errorlist.append(ticker)
    else:
        pass
    pass

謝謝，

乙

我找到了可行的解決方案！ 我刪除了兩個無關的urlopen和readlines命令，只為循環留了一個（在我只刪除urlopen命令之前，但保留了readlines）。 這是我的更正代碼：

def scrubdividata(ticker):
try:
    f = urllib2.urlopen('http://dividata.com/stock/%s'%(ticker))
    lines = f.readlines()
    for i in range(0,len(lines)):
        line = lines[i]
        if "Annual Dividend:" in line:
            s = str(lines[i+1])
            start = '>\$'
            end = '</td>'
            AnnualDiv = re.search('%s(.*)%s' % (start, end), s).group(1)
    #f = urllib2.urlopen('http://dividata.com/stock/%s'%(ticker))
    #lines = f.readlines()
    for i in range(0,len(lines)):
        line = lines[i]
        if "Last Dividend:" in line:
            s = str(lines[i+1])
            start = '>\$'
            end = '</td>'
            LastDiv = re.search('%s(.*)%s' % (start, end), s).group(1)
    #f = urllib2.urlopen('http://dividata.com/stock/%s'%(ticker))
    #lines = f.readlines()
    for i in range(0,len(lines)):
        line = lines[i]
        if "Last Ex-Dividend Date:" in line:
            s = str(lines[i+1])
            start = '>'
            end = '</td>'
            LastExDivDate = re.search('%s(.*)%s' % (start, end), s).group(1)
    divlist.append((ticker,LastDiv,AnnualDiv,LastExDivDate))
    print '@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@'
print ticker,LastDiv,AnnualDiv,LastExDivDate
print '@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@'
except:
    if ticker not in errorlist:
        errorlist.append(ticker)
    else:
        pass
    pass

Answer 1

BeautifulSoup示例供參考（內存中的Python2：在這里我僅將其用於Python3，因此某些語法可能會有所偏離）：

from BeautifulSoup import BeautifulSoup
from urllib2 import urlopen

yoursite = "http://...."
with urlopen(yoursite) as f:
    soup = BeautifulSoup(f)

    for node in soup.findAll('td', attrs={'class':'descrip'}):
        print node.text
        print node.next_sibling.next_sibling.text

輸出（對於示例輸入“ GOOG”）：

Last Close:
$910.68
Annual Dividend:
N/A
Pay Date:
N/A
Dividend Yield:
N/A
Ex-Dividend Date:
N/A
Years Paying:
N/A
52 Week Dividend:
$0.00
etc.

在具有可預測模式的網站上，BeautifulSoup易於使用。

Answer 2

def scrubdividata(ticker):
try:
    end = '</td>'
    f = urllib2.urlopen('http://dividata.com/stock/%s'%(ticker))
    lines = f.readlines()
    for i in range(0,len(lines)):
        line = lines[i]
        if "Annual Dividend:" in line:
            s = str(lines[i+1])
            start = '>\$'
            AnnualDiv = re.search('%s(.*)%s' % (start, end), s).group(1)
        if "Last Dividend:" in line:
            s = str(lines[i+1])
            start = '>\$'
            LastDiv = re.search('%s(.*)%s' % (start, end), s).group(1)
        if "Last Ex-Dividend Date:" in line:
            s = str(lines[i+1])
            start = '>'
            LastExDivDate = re.search('%s(.*)%s' % (start, end), s).group(1)
    divlist.append((ticker,LastDiv,AnnualDiv,LastExDivDate))
except:
    if ticker not in errorlist:
        errorlist.append(ticker)
    else:
        pass
    pass

Answer 3

需要注意的是lines會包含你所需要的線，所以沒有必要調用f.readlines()一次。 只需重復使用lines

小提示：您可以for line in lines使用for line in lines ：

def scrubdividata(ticker):
  try:
    f = urllib2.urlopen('http://dividata.com/stock/%s'%(ticker))
    lines = f.readlines()
    for line in lines:
        if "Annual Dividend:" in line:
            s = str(lines[i+1])
            start = '>\$'
            end = '</td>'
            AnnualDiv = re.search('%s(.*)%s' % (start, end), s).group(1)

    for line in lines:
        if "Last Dividend:" in line:
            s = str(lines[i+1])
            start = '>\$'
            end = '</td>'
            LastDiv = re.search('%s(.*)%s' % (start, end), s).group(1)

    for line in lines:
        if "Last Ex-Dividend Date:" in line:
            s = str(lines[i+1])
            start = '>'
            end = '</td>'
            LastExDivDate = re.search('%s(.*)%s' % (start, end), s).group(1)
    divlist.append((ticker,LastDiv,AnnualDiv,LastExDivDate))
  except:
    if ticker not in errorlist:
        errorlist.append(ticker)
    else:
        pass
    pass