Maintaining string length by adding zeros

Question

I need to pass a string with at least has a length of 10. How do I add 0's to fill the remaining blank spaces so it will always have a length of 10?

This is what I tried but does not work as expected.

var passString = "Abcdefg";
if (passString.length<10){
      var len = passString.length;
      var missing = 10-len;
      passString = passString + Array(missing).join("0")
}

try `(passString + Array(11).join('0')).substr(0,10)` ... no wait, that will limit to 10 regardless) — Jaromanda X, Dec 01 '15 at 13:43
@JaromandaX `it limits to 10 regardless` Not if checking for `passString.length<10` — A. Wolff, Dec 01 '15 at 13:47
http://stackoverflow.com/questions/2686855/is-there-a-javascript-function-that-can-pad-a-string-to-get-to-a-determined-lengt Same basic idea... — epascarello, Dec 01 '15 at 13:48

score 1 · Answer 1 · answered Dec 01 '15 at 13:45

1

please try below code

var passString = "Abcdefg";
if (passString.length<10){
      var len = passString.length;
      var missing = 10-len;
      passString =passString+  new Array(missing + 1).join("0");
}

thanks

answered Dec 01 '15 at 13:45

Ripun

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score 1 · Answer 2 · answered Dec 01 '15 at 13:46

1

You can do it in one line (I love giving one liners)

passString = (passString + Array(11).join('0')).substr(0,Math.max(10,passString.length))

answered Dec 01 '15 at 13:46

Jaromanda X

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epascarello · Accepted Answer · 2015-12-01T13:59:29.097

1

Concat zeros to the end of the string and use slice or substring or substr.

var passString = "ABC";
var fixed = (passString + "0000000000").slice(0,10);
console.log(fixed);

Based on comment, I skipped the if, but you can just do a basic if

var passString = "ABC";
var fixed = passString;
if (passString.length<10) {
    fixed = (passString + "0000000000").slice(0,10);
}
console.log(fixed);

or ternary operator

var passString = "ABC";
var fixed = passString >=10? passString : (passString + "0000000000").slice(0,10);
console.log(fixed);

or just override the original with an if

var passString = "ABC";
if (passString.length<10) {
    passString = (passString + "0000000000").slice(0,10);
}
console.log(passString);

edited Dec 01 '15 at 13:59

answered Dec 01 '15 at 13:52

epascarello

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My fav...Thank you! You're awesome! – Fergoso Dec 01 '15 at 13:54
The only issue is that it cuts of from 10. I need to maintain a minimum length of 10. Hope this makes scene. :) – Fergoso Dec 01 '15 at 13:56
Cool! that makes sense. :) – Fergoso Dec 01 '15 at 13:57

Maintaining string length by adding zeros

3 Answers3