Extract a number from a string (JavaScript)

Question

I have a string in JavaScript like #box2 and I just want the 2 from it.

I tried:

var thestring = $(this).attr(\'href\');
var          


        

Answer 1

You can do a function like this

function justNumbers(string) 
    {
        var numsStr = string.replace(/[^0-9]/g,'');
        return parseInt(numsStr);
    }

remember: if the number has a zero in front of it, the int wont have it

Answer 2

If someone need to preserve dots in extracted numbers:

var some = '65,87 EUR';
var number = some.replace(",",".").replace(/[^0-9&.]/g,'');
console.log(number); // returns 65.87

Answer 3

You can use Underscore String Library as following

var common="#box"
var href="#box1"

_(href).strRight(common)

result will be : 1

See :https://github.com/epeli/underscore.string

DEMO:
http://jsfiddle.net/abdennour/Vyqtt/
HTML Code :

<p>
    <a href="#box1" >img1</a>
    <a href="#box2" >img2</a>
    <a href="#box3" >img3</a>
    <a href="#box4" >img4</a>
</p>
<div style="font-size:30px"></div>

JS Code :

var comm="#box"
$('a').click(function(){
  $('div').html(_($(this).attr('href')).strRight(comm))})

if you have suffix as following :

href="box1az" 

You can use the next demo :

http://jsfiddle.net/abdennour/Vyqtt/1/

function retrieveNumber(all,prefix,suffix){
 var left=_(all).strRight(prefix);
 return _(left).strLeft(suffix);

}

Answer 4

var elValue     = "-12,erer3  4,-990.234sdsd";

var isNegetive = false;
if(elValue.indexOf("-")==0) isNegetive=true;

elValue     = elValue.replace( /[^\d\.]*/g, '');
elValue     = isNaN(Number(elValue)) ? 0 : Number(elValue);

if(isNegetive) elValue = 0 - elValue;

alert(elValue); //-1234990.234

Answer 5

You can use regular expression.

var txt="some text 2";
var numb = txt.match(/\d/g);
alert (numb);

That will alert 2.

Answer 6

You can extract numbers from a string using a regex expression:

let string = "xxfdx25y93.34xxd73";
let res = string.replace(/\D/g, "");
console.log(res); 

output: 25933473