Python：隔离re.search结果

2019年8月6日 142次阅读

所以我有这个代码(可能超级低效,但这是另一个故事),它从博客的
HTML代码中提取网址.我有一个.csv中的html,我将它放入
python中,然后运行正则表达式以获取URL.这是代码：

import csv, re # required imports

infile = open('Book1.csv', 'rt')  # open the csv file
reader = csv.reader(infile)  # read the csv file


strings = [] # initialize a list to read the rows into

for row in reader: # loop over all the rows in the csv file 
    strings += row  # put them into the list

link_list = []  # initialize list that all the links will be put in
for i in strings:  #  loop over the list to access each string for regex (can't regex on lists)

    links = re.search(r'((https?|ftp)://|www\.)[^\s/$.?#].[^\s]*', i) # regex to find the links
    if links != None: # if it finds a link..
        link_list.append(links) # put it into the list!

for link in link_list: # iterate the links over a loop so we can have them in a nice column format
    print(link)

但是,当我打印结果时,它的工作原理是：

<_sre.SRE_Match object; span=(49, 80), match='http://buy.tableausoftware.com"'>
<_sre.SRE_Match object; span=(29, 115), match='https://c.velaro.com/visitor/requestchat.aspx?sit>
<_sre.SRE_Match object; span=(34, 117), match='https://www.tableau.com/about/blog/2015/6/become->
<_sre.SRE_Match object; span=(32, 115), match='https://www.tableau.com/about/blog/2015/6/become->
<_sre.SRE_Match object; span=(76, 166), match='https://www.tableau.com/about/blog/2015/6/become->
<_sre.SRE_Match object; span=(9, 34), match='http://twitter.com/share"'>

有没有办法让我从包含的其他废话中拉出链接？那么,这只是正则表达式搜索的一部分吗？谢谢！

最佳答案 这里的问题是re.search返回
match object而不是匹配字符串,你需要使用
group属性来访问你想要的结果.

如果您想要所有捕获的组,则可以使用组属性,对于特殊组,您可以将预期组的数量传递给它.

在这种情况下似乎你想要整个匹配,所以你可以使用group(0)：

for i in strings:  #  loop over the list to access each string for regex (can't regex on lists)

    links = re.search(r'((https?|ftp)://|www\.)[^\s/$.?#].[^\s]*', i) # regex to find the links
    if links != None: # if it finds a link..
        link_list.append(links.group(0))

group([group1, …])

Returns one or more subgroups of the match. If there is a single argument, the result is a single string; if there are multiple arguments, the result is a tuple with one item per argument. Without arguments, group1 defaults to zero (the whole match is returned). If a groupN argument is zero, the corresponding return value is the entire matching string; if it is in the inclusive range [1..99], it is the string matching the corresponding parenthesized group. If a group number is negative or larger than the number of groups defined in the pattern, an IndexError exception is raised. If a group is contained in a part of the pattern that did not match, the corresponding result is None. If a group is contained in a part of the pattern that matched multiple times, the last match is returned.

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