从字符串中删除最后一个跨

Question

我有这个字符串：

"<span class='break'><div class='name-and-date'><strong>Mr. Talon 
 Williamson - Dec 18,  1:47 PM Eastern</div></strong><div class='note-
 contents'>- wrong</div></span><span class='break'><div class='name-and-
 date'><strong>Mr. Talon Williamson - Dec 18,  1:47 PM Eastern</div>
 </strong><div class='note-contents'>- Wrong again</div></span><span 
 class='break'><div class='name-and-date'><strong>Mr. Talon Williamson 
 - Dec 18,  1:47 PM Eastern</div></strong><div class='note-contents'>- 
 okay what is the matter with you.</div></span><span class='break'><div 
 class='name-and-date'><strong>Mr. Talon Williamson - Dec 18,  1:50 PM 
 Eastern</div></strong><div class='note-contents'>- Bro!</div></span>"

如何从此字符串中删除最后一个跨度，以便获得此返回值：

"<span class='break'><div class='name-and-date'><strong>Mr. Talon 
 Williamson - Dec 18,  1:47 PM Eastern</div></strong><div class='note-
 contents'>- wrong</div></span><span class='break'><div class='name-and-
 date'><strong>Mr. Talon Williamson - Dec 18,  1:47 PM Eastern</div>
 </strong><div class='note-contents'>- Wrong again</div></span><span 
 class='break'><div class='name-and-date'><strong>Mr. Talon Williamson 
 - Dec 18,  1:47 PM Eastern</div></strong><div class='note-contents'>- 
 okay what is the matter with you.</div></span>"

我理解使用Nokogiri进行html解析是更好的做法，但对于我的用例，保持字符串的完整性非常重要。这意味着除了删除最后一个跨度之外，它必须完全相同。

我想做这样的事情：

string.scan(/<span class='break'>/)

但是这并没有抓住整个字符串并将它们分解为数组元素。

NOTE: I asked a similar question earlier and I appreciate the help but it wasn't quite what I needed.

Answer 1

看看这是否有帮助。这是你在找什么？

txt = "<span class='break'><div class='name-and-date'><strong>Mr. Talon 
 Williamson - Dec 18,  1:47 PM Eastern</div></strong><div class='note-
 contents'>- wrong</div></span><span class='break'><div class='name-and-
 date'><strong>Mr. Talon Williamson - Dec 18,  1:47 PM Eastern</div>
 </strong><div class='note-contents'>- Wrong again</div></span><span 
 class='break'><div class='name-and-date'><strong>Mr. Talon Williamson 
 - Dec 18,  1:47 PM Eastern</div></strong><div class='note-contents'>- 
 okay what is the matter with you.</div></span><span class='break'><div 
 class='name-and-date'><strong>Mr. Talon Williamson - Dec 18,  1:50 PM 
 Eastern</div></strong><div class='note-contents'>- Bro!</div></span>"

txt.rindex('<span')
# => 540 
txt.rindex('</span')
# => 700 
txt[txt.rindex('<span'), txt.rindex('</span')]
# => "<span class='break'><div \n class='name-and-date'><strong>Mr. Talon Williamson - Dec 18,  1:50 PM \n Eastern</div></strong><div class='note-contents'>- Bro!</div></span>" 
txt[txt.rindex('<span'), txt.rindex('</span')] = ""
txt
# => "<span class='break'><div class='name-and-date'><strong>Mr. Talon \n Williamson - Dec 18,  1:47 PM Eastern</div></strong><div class='note-\n contents'>- wrong</div></span><span class='break'><div class='name-and-\n date'><strong>Mr. Talon Williamson - Dec 18,  1:47 PM Eastern</div>\n </strong><div class='note-contents'>- Wrong again</div></span><span \n class='break'><div class='name-and-date'><strong>Mr. Talon Williamson \n - Dec 18,  1:47 PM Eastern</div></strong><div class='note-contents'>- \n okay what is the matter with you.</div></span>"

Answer 2

你可以通过很多方式做到这一点。

假设你在txt变量中有那个字符串，那么txt.split("<span class='break'")[0..-2].join("<span class='break")就可以轻松工作了。这只是一个问题。

Answer 3

除非有嵌套的spans具有类"break"，否则以下内容将起作用。

input.scan(%r|<span\s+class=['"]break["']>.*?</span>|m)[0...-1].join

稍慢，但总是按预期工作：

input[%r|.*(?=<span\s+class=['"]break["']>.*?</span>\z)|m]

后一个解决方案使用positive lookahead来捕获所有内容，除了最后一个模式后紧跟字符串结尾（\z。）

关于String#[]的更多信息，以正则表达式作为参数。