JavaScript add space to a string after 2 characters but ignore newline character

I have to insert a space after every two characters in a string but by completely ignoring the newline character. I am able to do the spacing part but the problem comes with the newline as that is also counted as a character and when rendering the string it adds space at wrong positions.

<!-- begin snippet: js hide: false console: true babel: false -->

<!-- language: lang-js -->

let str = '23456\n734526754'
console.log(str)

str = str.match(/.{2}/g).join(' ');
console.log(str)

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For the above code the output comes as

23 45 67 
3 45 26 75 3

What should be the ideal output is

23 45 67 
34 52 67 53

How can I ignore the newline character completely?

You need to update your code.

<!-- begin snippet: js hide: false console: true babel: false -->

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let str = '234562\n7345267542';
str = str.replace(/(.{2})/g, "$1 ").trim();
console.log(str);

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Solution details :

1. expression .{2} matches two characters
2. $1 is for adding space after each group of 2 character
3. g is for match all values
4. trim method removes any leading and trailing whitespace from string

You may use this spacer function in Javascript:

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function spacer(s) {
   return s
     .replace(/^((?:.{2})*.)\n(.)(.*)/g, '$1$2\n$3')
     .replace(/.{2}(?=.)/g, '$& ');
}

console.log(spacer('23456\n734526754'));
//=> '23 45 67\n34 52 67 54'

console.log(spacer('234562\n7345267542'));
//=> '23 45 62\n73 45 26 75 42'

<!-- end snippet -->

Solution Details:

• spacer function user 2 .replace invocations
• First .replace finds \n after matching odd number of characters and moves it one position ahead using 3 capture groups
• Second .replace matches a pair of any characters (except line break) and inserts a space after the match

Here is an approach using a single regex replacement:

<!-- begin snippet: js hide: false console: true babel: false -->

<!-- language: lang-js -->

var str = '23456\n734526754';
var output = str.replace(/(\S{1,2})(?=\S)/g, "$1 ");
console.log(output);

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The regex pattern used here says to match:

• (\S{1,2}) match AND capture either 1 or 2 non whitespace characters
• (?=\S) assert that non whitespace follows (do not add space after final group)

Then, we replace with $1 to effectively add a space after each group.