Question

I have seen a bunch of JavaScript validation tutorials which validate your input as you type.

E.g.: http://reactiveraven.github.com/jqBootstrapValidation/

However they all seem to be constantly validating, which could prove annoying to end-users.

Can I make it validate only after you’ve tabbed to the next <input>,<button> or <a>?

[using pure JS, no JQuery or other library]

Answer 1

Sure. You’d want to use the onblur event on your element.

elem.addEventListener('blur', validateInput, false); // validateInput being your validation function