How can you check for a #hash in a URL using JavaScript?

Question

I have some jQuery/JavaScript code that I want to run only when there is a hash (#) anchor link in a URL. How can you check for this character using JavaScript?

Answer 1

Here is a simple function that returns true or false (has / doesn't have a hashtag):

var urlToCheck = 'http://www.domain.com/#hashtag';

function hasHashtag(url) {
    return (url.indexOf("#") != -1) ? true : false;
}

// Condition
if(hasHashtag(urlToCheck)) {
    // Do something if has
}
else {
    // Do something if doesn't
}

Returns true in this case.

Based on @jon-skeet's comment.