如何在 JavaScriptRegexp 中捕获任意数量的组？

小开

How's about this? "foo bar baz".match(/(\w+)+/g)

小开

Unless you have a more complicated requirement for how you're splitting your strings, you can split them, and then return the initial string with them:

var data = "foo bar baz";
var pieces = data.split(' ');
pieces.unshift(data);

小开

最佳答案

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.

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.

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

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
Do multilevel matching:
- Capture the repeated group in one match
- Then run another regex to break that match apart

References

regular-expressions.info/Repeating a Capturing Group vs Capturing a Repeating Group
- Javascript flavor notes

Example

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

The pattern used is:

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

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 JavaScriptRegexp 中捕获任意数量的组？

References

Example

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