Question

Is there any way to find out the longest word in Javascript? It should ignore punctuation marks too!

I understood the logic, but the code… sigh

Here’s what we do –

1. Count the number of alphanumeric characters that are together, not separated by a space or any sign.

2. Get their lengths.

3. Find the biggest length in all.
4. Return the word with the biggest length.

Hope I’m making myself clear…

Answer 1

Split the string, loop over the parts and keep track of the longest one.

Something like this:

var parts = sentence.split();
var longestIndex = -1;
var longestWord = 0;

for(var i=0; i < parts.length; i++){
    if(parts[i].length > longestWord){
        longestWord = parts[i].length;
        longestIndex = i;
    }
}

alert("longest word is " + parts[longestIndex] + ": " + longestWord + " characters");

If you need to split on non alphabetic characters as well as spaces you need to use regexes. You can change this line:

var parts = sentence.split();

To this (thanks Kooilnc for the regex):

var parts = sentence.match(/\w[a-z]{0,}/gi);

Working jsfiddle