javascript string character manipulation

Question

My challenge is to create a function that takes in a string and returns a new string with each character advanced 1 space of the alphabet. Ex: "hello" returns "ifmmp."

I haven't yet wrapped my code in a function. This will get me the first new character but I can't figure out how to move through the rest of the new characters.

var str = "hello";

var numStr = [];

for (var i = 0; i < str.length; i++) {

    numStr.push((str.charCodeAt(i) + 1));

}

var newStr = String.fromCharCode(numStr[0]);

//returns "i"

You may use `+` operator to add strings so `'a' + 'b'` gives you `'ab'`. Use a for loop to build `newStr` like `var newStr = ''; for (var i = 0; ....) { newStr += String.fromCharCode(numStr[i]); }`. `newStr += x` is like `newStr = newStr + x` — csharpfolk, Mar 08 '16 at 19:01

score 2 · Accepted Answer · answered Mar 08 '16 at 19:06

2

You'll probably want to use fromCharCode(). Creating a function could look something like this:

JavaScript

var str = "hello";

function incrementStringLetters(s) {
    var newStr = "";
    for (var i = 0; i < s.length; i++) {
        newStr += String.fromCharCode(s.charCodeAt(i)+1);
    }
    return newStr;
}


console.log(incrementStringLetters(str))

Output

ifmmp

See it working here: https://jsfiddle.net/igor_9000/f0vy3h9v/

Hope that helps!

answered Mar 08 '16 at 19:06

Adam Konieska

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Fantastic, thank you! I couldn't figure out how to use the fromCharCode function like this. – adam.shaleen Mar 08 '16 at 19:42

score 0 · Answer 2 · answered Mar 08 '16 at 19:10

Another proposal with:

var str = "hello",
    newStr = str.split('').map(function (a) {
        return String.fromCharCode(a.charCodeAt(0) + 1);
    }).join('');

document.write(newStr);

javascript string character manipulation

2 Answers2