Check if a JavaScript string is a URL

Question

Is there a way in JavaScript to check if a string is a URL?

RegExes are excluded because the URL is most likely written like stackoverflow; that is to s

Answer 1

There's a lot of answers already, but here's another contribution: Taken directly from the URL polyfill validity check, use an input element with type="url" to take advantage of the browser's built-in validity check:

var inputElement = doc.createElement('input');
inputElement.type = 'url';
inputElement.value = url;

if (!inputElement.checkValidity()) {
    throw new TypeError('Invalid URL');
}

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