open1= testO.finditer(line) for m in open1: #print('opening:',m.group().replace('<', '').replace('>', '')) firstm= m.group().replace('<', '').replace('>', '').split() num = 0 for otherm in firstm: if num == 0: print('opening:',otherm) else: print('pram:',otherm) num+= 1
Salin selepas log masuk
在正则表达式中，可以使用反向引用来指示匹配早期部分的子字符串,应再次出现正则表达式的。格式为\N（其中N为正整数），并返回到第N个匹配的文本正则表达式组。例如，正则表达式，如：r" (\w+) \1 仅当与组（\w+）完全匹配的字符串再次出现时才匹配 backref\1出现的位置。这可能与字符串“踢”匹配.例如，“the”出现两次。使用反向引用编写一个模式，当一行包含成对的open和关闭标签，例如在粗体中.
考虑到我们可能想要创建一个执行HTML剥离的脚本，即一个HTML文件，并返回一个纯文本文件，所有HTML标记都已从中删除出来这里我们不打算这样做，而是考虑一个更简单的例子，即删除我们在输入数据文件的任何行中找到的HTML标记。
import sys, re #------------------------------ # PART 1: # Key thing is to avoid matching strings that include # multiple tags, e.g. treating '' as a single # tag. Can do this in several ways. Firstly, use # non-greedy matching, so get shortest possible match # including the two angle brackets: tag = re.compile('') # The above treats the '/' of a close tag as a separate # optional component - so that this doesn't turn up as # part of the match '.group(1)', which is meant to return # the tag label. # Following alternative solution uses a negated character # class to explicitly prevent this including '>': tag = re.compile(']+)>') # Finally, following version separates finding the tag # label string from any (optional) parameters that might # also appear before the close angle bracket: tag = re.compile(r']+)?>') # Note that use of '\b' (as word boundary anchor) here means # we must mark the regex string as a 'raw' string (r'..'). #------------------------------ # PART 2: # Following closeTag definition requires first first char # after the open angle bracket to be '/', while openTag # definition excludes this by requiring first char to be # a 'word char' (\w): openTag = re.compile(r'<(\w[^>]*)>') closeTag = re.compile(r']*)>') # Following revised definitions are more carefully stated # for correct extraction of tag label (separately from # any parameters: openTag = re.compile(r'<(\w+\b)([^>]+)?>') closeTag = re.compile(r'') #------------------------------ # PART 3: # Above openTag definition will already get the string # encompassing any parameters, and return it as # m.group(2), i.e. defn: openTag = re.compile(r'<(\w+\b)([^>]+)?>') # If assume that parameters are continuous non-whitespace # chars separated by whitespace chars, then we can divide # them up using split - and that's how we handle them # here. (In reality, parameter strings can be a lot more # messy than this, but we won't try to deal with that.) #------------------------------ # PART 4: openCloseTagPair = re.compile(r'<(\w+\b)([^>]+)?>(.*?)') # Note use of non-greedy matching for the text falling # *between* the open/close tag pair - to avoid false # results where have two similar tag pairs on same line. #------------------------------ # PART 5: URLS # This is quite tricky. The URL expressions in the file # are of two kinds, of which the first is a string # between double quotes ("..") which may include # whitespace. For this case we might have a regex: url = re.compile('href=("[^">]+")', re.I) # The second case does not have quotes, and does not # allow whitespace, consisting of a continuous sequence # of non-whitespace material (that ends when you reach a # space or close bracket '>'). This might be: url = re.compile('href=([^">\s]+)', re.I) # We can combine these two cases as follows, and still # get the expression back as group(1): url = re.compile(r'href=("[^">]+"|[^">\s]+)', re.I) # Note that I've done nothing here to exclude 'mailto:' # links as being accepted as URLS. #------------------------------ with open('RGX_DATA.html') as infs: linenum = 0 for line in infs: linenum += 1 if line.strip() == '': continue print(' ', '-' * 100, '[%d]' % linenum, '\n TEXT:', line, end='') # PART 1: find HTML tags # (The following uses 'finditer' to find ALL matches # within the line) mm = tag.finditer(line) for m in mm: print('** TAG:', m.group(1), ' + [%s]' % m.group(2)) # PART 2,3: find open/close tags (+ params of open tags) mm = openTag.finditer(line) for m in mm: print('** OPENTAG:', m.group(1)) if m.group(2): for param in m.group(2).split(): print(' PARAM:', param) mm = closeTag.finditer(line) for m in mm: print('** CLOSETAG:', m.group(1)) # PART 4: find open/close tag pairs appearing on same line mm = openCloseTagPair.finditer(line) for m in mm: print("** PAIR [%s]: \"%s\"" % (m.group(1), m.group(3))) # PART 5: find URLs: mm = url.finditer(line) for m in mm: print('** URL:', m.group(1)) # PART 6: Strip out HTML tags (note that .sub will do all # possible substitutions, unless number is limited by count # keyword arg - which is fortunately what we want here) stripped = tag.sub('', line) print('** STRIPPED:', stripped, end = '')
Salin selepas log masuk
Atas ialah kandungan terperinci Cara menggunakan ungkapan biasa dalam Python untuk memproses fail html. Untuk maklumat lanjut, sila ikut artikel berkaitan lain di laman web China PHP!
![[Web front-end] Permulaan pantas Node.js](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
