remove values from a string

Question

Does anyone know how I would remove all leading zeros from a string.

var str = 000890

The string value changes all the time so I need it to be able to remove all 0s before a number greater than 0. So in the example above it needs to remove the first three 0s. So the result would be 890

JesseBuesking · Answer 1 · 2011-12-16T22:22:25.617

9

It looks like we each have our own ways of doing this. I've created a test on jsperf.com, but the results are showing

String(Number('000890'));

is the quickest (on google chrome).

enter image description here

Here are the numbers for the updated test based on @BenLee's comment for Firefox, IE, and Chrome.

enter image description here

edited Dec 16 '11 at 22:22

answered Dec 16 '11 at 20:27

JesseBuesking

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For my Chrome 16 (for Linux), I am getting much closer performance for options 2 and 3 than you are (my results are regex: 5mm, classes: 17mm, parseInt: 15mm, typecasting: 22mm) – Ben Lee Dec 16 '11 at 20:37
1

Oh, I should mention I'm the one that added the 4th test for `'' + +str`, which turns out to actually be the fastest contender, outperforming the next fastest by about 50% and outperforming the slowest by a factor of 5. – Ben Lee Dec 16 '11 at 20:38

score 5 · Answer 2 · edited May 23 '17 at 10:30

5

See: this question

var resultString = str.replace(/^[0]+/g,"");

edited May 23 '17 at 10:30

Community

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answered Dec 16 '11 at 20:08

Anders

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score 4 · Accepted Answer · answered Dec 16 '11 at 20:08

4

var resultString = str.replace(/^[0]+/g,"");

answered Dec 16 '11 at 20:08

Zoltan Toth

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sorry about that... apparently we think alike. – Anders Dec 16 '11 at 20:09
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@Anders no worries - smart people tend to think alike :) – Zoltan Toth Dec 16 '11 at 20:12
Luck of the draw, congrats ;) – Anders Dec 16 '11 at 20:39
The square braces are optional. The global flag is unnecessary, since only one "beginning of a string" can exist. The following pattern will do: `/^0+/`. – Rob W Dec 16 '11 at 20:59

score 2 · Answer 4 · answered Dec 16 '11 at 20:09

2

I think a function like this should work

   function replacezeros(text){    
      var newText = text.replace(/^[0]+/g,"");
      return newText;
}

answered Dec 16 '11 at 20:09

Dominic Green

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new i would get beaten to the punch on this one – Dominic Green Dec 16 '11 at 20:10

score 2 · Answer 5 · answered Dec 16 '11 at 20:14

2

If it needs to stay as a string, cast it to a number, and cast it back to a string:

var num = '000123';
num = String(Number(num));
console.log(num);

You could also use the shorthand num = ''+(+num);. Although, I find the first form to be more readable.

answered Dec 16 '11 at 20:14

zzzzBov

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+1 for simultaneously posting what I think is the cleanest-looking solution `String(Number(num))` as well as what turns out to be the fastest-peforming solution `''+(+num)` (see JesseB's answer for confirmation on that) – Ben Lee Dec 16 '11 at 20:52

Ben Lee · Answer 6 · 2011-12-16T20:30:37.880

If your problem really is as you defined it, then go with one of the regex-based answers others have posted.

If the problem is just that you have a zero-padded integer in your string and need to manipulate the integer value without the zero-padding, you can just convert it to an integer like this:

parseInt("000890", 10) # => 890

Note that the result here is the integer 890 not the string "890". Also note that the radix 10 is required here because the string starts with a zero.

score 2 · Answer 7 · answered Dec 16 '11 at 20:18

2

parseInt('00890', 10); // returns 890
// or
Number('00890'); // returns 890

answered Dec 16 '11 at 20:18

Troy Watt

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score 1 · Answer 8 · answered Dec 16 '11 at 20:28

1

return str.replace(/^0+(.)/, '$1'));

That is: replace maximum number of leading zeros followed by any single character (which won't be a zero), with that single character. This is necessary so as not to swallow up a single "0"

answered Dec 16 '11 at 20:28

smendola

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score -1 · Answer 9 · answered Dec 16 '11 at 20:11

-1

you can simply do that removing the quotation marks.

var str = 000890;
//890
var str = "000890";
//000890

answered Dec 16 '11 at 20:11

Eduardo Moniz

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remove values from a string

9 Answers9