When you're doing Ajax-based validation on a text input control, you really don't want your data calls firing off at every keyup event as this will put unnecessary load on your server. Instead, the thing to do is to wait a little while after the user's last key release to see if she's stopped typing before firing off a request.

I'm sure that there are hundreds of code snippets lying about for doing just this, and that JQuery probably already has something built in or a plugin for it, but a quick Google search didn't turn up anything for me so here I am, sharing my simple solution for delayed Ajax validation in JavaScript.

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