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Ricardo A
Asked: 2020-06-27 18:48:21 +0800 CST 2020-06-27 18:48:21 +0800 CST

How can I reverse the order of the string given in the parameter?

  • 772

I know I have to use .reverse(); and I imagine that the first thing I have to do is also pass the string given in the parameter to an array, but I don't know how I could do it or in what order. I leave my code below.

function reverseString(str) {
  return str;
}

reverseString("hello");

Beforehand thank you very much.

(What I want is that if I put "hello" as a parameter when returning the value it says "olleh").

javascript

1 Answers

  1. Best Answer

    This is a method to do what you want:

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

alert(reverseString("hello"));

    I am writing you a method since there are actually different ways to do this, I recommend this article, where you can find 10 ways to do it, made by Edd Mann : http://eddmann.com/posts/ten-ways-to-reverse -a-string-in-javascript/

    1: Decrementing for-loop with concatenation

    function reverse(s) {
  var o = '';
  for (var i = s.length - 1; i >= 0; i--)
    o += s[i];
  return o;
}

alert(reverse("hello"));

    ...
...
...

    10:

    function reverse(s) {
  if (s.length < 2)
    return s;
  var halfIndex = Math.ceil(s.length / 2);
  return reverse(s.substr(halfIndex)) + reverse(s.substr(0, halfIndex));
}

alert(reverse("hello"));

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