Javascript adding a leading zero to all single digit numbers in a string [closed]

Question

var string = "name t13 - cat y4 - dat s6";

should be changed to "name t13 - cat y04 - dat s06"

I need the string to always have at least two digit numbers. How can I change numbers within a string to lead with a zero if there is a single digit?

Answer 1

String.prototype. replace() String.prototype. replace() accepts a regular expression as the first argument for pattern matching. You can also supply a function as the second argument which is called for each match and returns a replacement value.

 var tests = [ "s61 t1 e32 w2 i5 e600", "name t13 - cat y4 - dat s6", "others13y4sixs6" ]; tests.forEach(function(test){ console.log(test.replace(/\\D\\d(?!\\d+)/g, function(c) { return c.charAt(0) + "0" + c.charAt(1); })); });