JavaScript - swap first and last character in every word in string

In this article, we would like to show you how to swap the first and last character in every word in a string in JavaScript.

Quick solution:

// ONLINE-RUNNER:browser;

const text = 'This is example text';

const result = text
    .split(' ')
    .map((word) => {
        if (word.length > 1) {
            word = word[word.length - 1] + word.substring(1, word.length - 1) + word[0];
        }
        return word;
    })
    .join(' ');

console.log(result);

Reusable function

In this example, we create a reusable function that splits given text into an array of words, swaps each word's first and last letter, and joins them back into the string.

// ONLINE-RUNNER:browser;

const swapFirstAndLast = (text) => {
    return text
        .split(' ')
        .map((word) => {
            if (word.length > 1) {
                word = word[word.length - 1] + word.substring(1, word.length - 1) + word[0];
            }
            return word;
        })
        .join(' ');
};


// Usage example
const text = 'This is example text';

console.log(swapFirstAndLast(text));

Output:

shiT si example text

References

1. String.prototype.split() - JavaScript | MDN
2. Array.prototype.map() - JavaScript | MDN
3. String.prototype.substring() - JavaScript | MDN
4. Array.prototype.join() - JavaScript | MDN