javascript regex replace at the end of string

Question

I have following string:

text = '20 as a % of 50'

I need to replace it using a regular expression, the result should be:

'20 / 50 * 100'

How can I do this?

Can you give another example? I can't get the regular pattern from this one — wong2
– wong2, Commented Apr 5, 2011 at 9:17
sounds like you're trying to hack an "are you a human" portion of a form ;) — seanmetzgar
– seanmetzgar, Commented Jan 30, 2016 at 19:26

kapa · Accepted Answer · 2011-04-05 09:57:13Z

4

I created an example here: http://regexr.com?2tfam

You can match with (\d+) as a % of (\d+) and replace with $1 / $2 * 100.

var a="text = '20 as a % of 50'";
alert(a.replace(/(\d+) as a % of (\d+)/, '$1 / $2 * 100'));

I also created a jsFiddle.

EDIT: If your text between the numbers will change, you can use this regex:

(\d+)[%a-zA-Z ]+(\d+)

It assumes that the operator is % and between the numbers only letters and spaces can occur.

answered Apr 5, 2011 at 9:21

kapa

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1 Comment

thanks, and what if between two numbers can be chars, for example 100 usd as a % of 200 usd, and i need to keep usd in str?

niksvp · Accepted Answer · 2011-04-05 09:28:57Z

0

This should help you,

var str="20 as a % of 50"; 
var patt1=/(\d)+/g;
alert(str.match(patt1)[0]+ "/"+ str.match(patt1)[1] + "* 100");

answered Apr 5, 2011 at 9:28

niksvp

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