Can't make a regular expression to work

Question

var textoNotes = "e|-----------------|B|-----------------|G|-----------------|D|-----------------|A|-----------------|E|3-3-3-3-3-3-3-3-3|"; var filterChords = /(\(|[^(e|B|G|D|A|E)|]+|\))/g; var arr = filterChords.exec(textoNotes);

This returns:

arr[0] = ----------------- arr[1] = -----------------

but, This is what I want:

arr[0] = ----------------- arr[1] = ----------------- arr[2] = ----------------- arr[3] = ----------------- arr[4] = ----------------- arr[5] = 3-3-3-3-3-3-3-3-3

Thanks you all, and after this I want to get each value in a diferent value.

Have you tested your regex on regex101.com? It looks fine, if I understood you correctly. — Emre Türkiş
– Emre Türkiş, Commented Oct 13, 2015 at 13:48

Wiktor Stribiżew · Accepted Answer · 2015-10-13 13:42:24Z

Note that your regex misbehaves as you tried to use groups inside a character class. In (\(|[^(e|B|G|D|A|E)|]+|\)), you have 3 alternatives:

1) \( matching a literak ( 2) [^(e|B|G|D|A|E)|]+ matching 1 or more characters other than (, e... 3) \) matching a literal ).

You can use the following regex:

[eBGDAE]\|[^|]+\|

See regex demo

The regex:

[eBGDAE] - matches 1 letter from the range
\| - matches a literal |
[^|]+ - 1 or more characters other than |
\| - 1 literal |.

Note that to make sure you match 1 letter in the beginning, you may use a \b word boundary:

\b[eBGDAE]\|[^|]+\|

JS snippet:

var re = /\b[eBGDAE]\|[^|]+\|/g; var str = 'e|-----------------|B|-----------------|G|-----------------|D|-----------------|A|-----------------|E|3-3-3-3-3-3-3-3-3|'; var res = []; while ((m = re.exec(str)) !== null) { res.push(m[0]); document.getElementById("r").innerHTML += m[0] + "<br/>"; }

<div id="r"/>

The res will contain the array of the values required, and document... is only for demo.

Brandon Deo · Accepted Answer · 2015-10-13 13:40:15Z

Your regular expression doesn't match what you want it seems. I would try using something like below (assuming I am understanding your question correctly, as it's a bit unclear).

text.match(/[e|B|G|D|A|E]\|(.+)\|/g);

str.match() will output an array of values.

A good place to test your regex is http://www.regexr.com or other similar site.

ergonaut · Accepted Answer · 2015-10-13 13:42:54Z

Why don't you try this:

text.match(/[^\|eBGDAE]+/g);

Which will just match any stream of characters not on this list including pipes?

hata · Accepted Answer · 2015-10-13 13:56:17Z

So | is one of the special characters that you should escape this which exists outside of [];

<script> var textoNotes = "e|-----------------|B|-----------------|G|-----------------|D|-----------------|A|-----------------|E|3-3-3-3-3-3-3-3-3|"; var filterChords = /[eBGDAE]\|[^eBGDAE|]+\|/g; var arr; while (arr = filterChords.exec(textoNotes)) { alert(arr); } </script>

Collectives™ on Stack Overflow

Can't make a regular expression to work

4 Answers 4

Comments

Comments

Comments

Comments

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

Comments

Comments

Comments

Related