这个正则表达式在做什么？

Question

I thought this regex was about turning words into an array, but I get null as a result

when I want to get the second word from "facebox otherword" with array[0]

This is the regex:

this.rel.match(/facebox\[?\.(\w+)\]?/)

Thanks Richard

Answer 1

http://xenon.stanford.edu/~xusch/regexp/analyzer.html is a simple regex analyzer (among many others). Since its not linkable , here is just a screenshot and the link :

Answer 2

I believe you are looking for is the split() function:

What you mentioned about turning words into an array is typically referred to as a split , so if you wanted to get " otherword " from " facebox otherword ", you would do the following:

var test = "facebox otherword"
var word = test.split(' ')[1];

Working Demo

Answer 3

Your regex matches:

facebox.abc
facebox[.abc
facebox[.abc]
facebox.abc]

with abc being at least one "word character" (letters, digits, and underscores).

Answer 4

Note \. . That means that it is a dot, rather than any character. This regex cathches facebox.otherword

Answer 5

This matches text like:

facebox[.blabla]
facebox.blabla

Answer 6

The regex you have there won't match "facebook otherword", because of the \. . It's looking for a literal ".", so it would match the following: "facebook.otherword", "facebook[.otherword", "facebook.otherword]", or "facebook[.otherword]".

Answer 7

Checks that the string contained in the rel property of this

1. contains the text 'facebox'
2. followed by 0 or 1 open-square-brackets
3. followed by a dot
4. followed by 1 or more word characters
5. followed by 0 or 1 close-square-brackets

If matched, the 1 or more word characters will be contained in a sub-match.

Answer 8

/facebox\[?\.(\w+)\]?/

• matches facebox literal
• then optionally match [
• then match .
• then match any word
• then optionally match ]