如何在JavaScript Regexp中捕获任意数量的组？ [英] How to capture an arbitrary number of groups in JavaScript Regexp?

问题描述

我希望这行JavaScript：

I would expect this line of JavaScript:

"foo bar baz".match(/^(\s*\w+)+$/)

返回类似于：

["foo bar baz", "foo", " bar", " baz"]

但它仅返回上次捕获的匹配：

but instead it returns only the last captured match:

["foo bar baz", " baz"]

有没有办法获得所有捕获的匹配？

Is there a way to get all the captured matches?

推荐答案

当您重复捕获组时，在大多数情况下，只保留最后一次捕获;以前的任何捕获都会被覆盖。在一些风味中，例如.NET，您可以获得所有中间捕获，但Javascript不是这种情况。

When you repeat a capturing group, in most flavors, only the last capture is kept; any previous capture is overwritten. In some flavor, e.g. .NET, you can get all intermediate captures, but this is not the case with Javascript.

也就是说，在Javascript中，如果你有 N的模式捕获组，每次匹配时只能捕获 N 字符串，即使其中一些组被重复。

That is, in Javascript, if you have a pattern with N capturing groups, you can only capture exactly N strings per match, even if some of those groups were repeated.

所以一般来说，取决于你需要做什么：

So generally speaking, depending on what you need to do:

• 如果这是一个选项，拆分为分隔符


• 而不是匹配 /（模式）+ / ，可能匹配 / pattern / g ，可能在 exec 循环
  
  
  
  
  • 请注意这两个不完全相同，但它可能是一个选项
  
  
  • If it's an option, split on delimiters instead
  • Instead of matching /(pattern)+/, maybe match /pattern/g, perhaps in an exec loop
    • Do note that these two aren't exactly equivalent, but it may be an option
    
    
    • 在一场比赛中捕获重复的组
    
    
    • 然后运行另一个正则表达式以区分该比赛
    
    
    
    
    • regular-expressions.info/重复捕获组与捕获重复组
      
      
      
      
      • Javascript风味笔记
      
      
      • regular-expressions.info/Repeating a Capturing Group vs Capturing a Repeating Group
        • Javascript flavor notes

        以下是匹配< some; words; here>的示例在文本中，使用 exec 循环，然后拆分; 以获得个人单词（另见ideone.com ）：

        Here's an example of matching <some;words;here> in a text, using an exec loop, and then splitting on ; to get individual words (see also on ideone.com):

        var text = "a;b;<c;d;e;f>;g;h;i;<no no no>;j;k;<xx;yy;zz>";
        
        var r = /<(\w+(;\w+)*)>/g;
        
        var match;
        while ((match = r.exec(text)) != null) {
          print(match[1].split(";"));
        }
        // c,d,e,f
        // xx,yy,zz
        

        使用的模式是：

              _2__
             /    \
        <(\w+(;\w+)*)>
         \__________/
              1
        

        匹配 < word> ，< word;另一个> ，< word;另一个;请> 等。重复组2以捕获任意数量的单词，但它只能保留最后一次捕获。整个单词列表由第1组捕获;这个字符串在分号分隔符上是 split 。

        This matches <word>, <word;another>, <word;another;please>, etc. Group 2 is repeated to capture any number of words, but it can only keep the last capture. The entire list of words is captured by group 1; this string is then split on the semicolon delimiter.

        
        
        • 如何在javascript正则表达式中访问匹配的组？
        
        
        • How do you access the matched groups in a javascript regex?

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