String of numbers can't start with zero. Other Solutions?

Question

I have a string that only contains numbers, but the string can not start with a zero.

The first thing I cam up with was this:

let myNumber = "0052";
myNumber = myNumber.split('');
for (let i = 0; i < myNumber.length; i++) {
    if (myNumber[i] == '0') {
        myNumber.splice(i, 1);
        i--;
    } else {
        break;
    }
}
console.log(myNumber);
console.log('result:', myNumber.join(''));

Everything works fine like that.

I thought there might be an other way without using a classical for-loop. My attempt with a for-of loop failed. As soon as I remove the first entry of my array, the index of the loop does not reset, so it skips the second zero in my array. Here is the code for that:

let myNumber = "0052";
myNumber = myNumber.split('');
for (let n of myNumber) {
    if (n == '0') {
        myNumber.shift();
    } else {
        break;
    }
}
console.log(myNumber);
console.log('result:', myNumber.join(''));

What other solutions to this problem are there? Is there a more performant solution?

So your spurce code works but you want to explore other methods/solutions? If so then your question is in the wrong place. — NewToJS, Feb 16 '18 at 21:11

score 5 · Answer 1 · answered Feb 16 '18 at 21:11

5

Regexp: /^[0]+/

let myNumber = "0000000520";
console.log(myNumber.replace(/^[0]+/, ''))

answered Feb 16 '18 at 21:11

Ele

33,468
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75

Tomasz Bubała · Accepted Answer · 2018-02-16T21:14:28.210

5

What you're probably looking for is parseInt function.

const result = parseInt("0052", 10).toString();
console.log(result);

I also added toString() to convert number to a string. parseInt also accepts second argument - the radix. Read more about parseInt

edited Feb 16 '18 at 21:14

answered Feb 16 '18 at 21:12

Tomasz Bubała

2,093
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18

This is probably the straightforward solution :-) – Ele Feb 16 '18 at 21:13
1

@Ele yes I think so. Since i'm not working with floats. Tomasz Thanks for your answer, Sometimes I just think way to far out of the box – JiiB Feb 16 '18 at 21:14
1

Sometimes the solution may be easier than we think! :) Take a look at @Ele 's answer as thinking with regex is also good in many situations – Tomasz Bubała Feb 16 '18 at 21:17
1

Bad idea even with specifying radix as 10? Good point though! – Tomasz Bubała Feb 16 '18 at 21:18

Martin · Answer 3 · 2018-02-16T21:18:45.053

1

Use parseInt('0052') = 52

or

parseFloat('0052.29') = 52.29 if your number is float type:

edited Feb 16 '18 at 21:18

answered Feb 16 '18 at 21:15

Martin

201
1
4

thanks for your answer, but @Tomasz already used parseInt – JiiB Feb 16 '18 at 21:16

score 0 · Answer 4 · answered Feb 16 '18 at 21:23

0

I just have different and simpler approach than yours :)

while(myNumber.length){
  if(myNumber.charAt(0) == '0')
    myNumber = myNumber.substring(1, myNumber.length);
}

DEMO : https://jsbin.com/falejuruwu/1/edit?js,console

answered Feb 16 '18 at 21:23

Ankush Malik

150
2
11

1

simpler: `while(myNumber.charAt(0) == '0') myNumber = myNumber.slice(1);` – Feb 16 '18 at 21:28
@doodlemeister yours better :) I forgot about slice – Ankush Malik Feb 16 '18 at 21:31

String of numbers can't start with zero. Other Solutions?

4 Answers4