How do you reverse a string in place in JavaScript?

javascript string reverse
Jake picture Jake · Jun 6, 2009 · Viewed 447k times · Source

How do you reverse a string in place (or in-place) in JavaScript when it is passed to a function with a return statement, without using built-in functions (.reverse(), .charAt() etc.)?

Answer

belacqua picture belacqua · Jun 6, 2009

As long as you're dealing with simple ASCII characters, and you're happy to use built-in functions, this will work:

function reverse(s){
    return s.split("").reverse().join("");
}

If you need a solution that supports UTF-16 or other multi-byte characters, be aware that this function will give invalid unicode strings, or valid strings that look funny. You might want to consider this answer instead.

[...s] is Unicode aware, a small edit gives:- 

function reverse(s){
    return [...s].reverse().join("");
}

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