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JavaScript

Posted by Ira Salem
Ira Salem
10,331 Points

Reversing a string in JS

I'm trying to reverse the string "hello" but I keep getting an error message with this code. What am I doing wrong? I know that I'll have to split the string first which should turn the string into an array that contains 'h','e','l','l', and 'o'. Then I reverse them and then join them back together but I can't even get past the first step.

function reverseString(str) {
  return str;
}

reverseString.split(("hello", ""));
Ira Salem
Ira Salem
10,331 Points

Here is my new code. I'm still not getting what I want. What am I doing wrong?

function reverseString(str) {
  var myArray = str.split(' ');
  myArray.reverse();
  return str;
}

var hello = 'Hello'
var howdy = 'Howdy'
var greetings = 'Greetings from Earth'

reverseString(hello);
reverseString(howdy);
reverseString(greetings);

2 Answers

Jacob Mishkin
Jacob Mishkin
23,118 Points

There are several ways you can do this. I suggest using the reverse() method, like so:

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

by returning the split() and reverse() and join() methods what is happing here is that you first split the string into array, then call the reverse() method, then you put it back together with the join() method.

there are a lot of other ways to reverse a string, but I think this is the most effective way. I hope this helps.

Ira Salem
Ira Salem
10,331 Points

Thank you so much. That worked perfectly

Jacob Mishkin
Jacob Mishkin
23,118 Points

Ira not a problem. Any time.

Andrew Dummer
Andrew Dummer
6,885 Points
Andrew Dummer
Andrew Dummer
6,885 Points

Ira, In your reverseString(), please try returning myArray instead of str and using str.split('') instead of str.split(' '). That should get you past your first step.