It appears JQuery Form Validation supports returning a string when using the remote validator but it’s not immediately clear how to do this and the examples tab doesn’t have an example for doing so. Getting this working is actually very easy. All you need to do is return a JavaScript string in your response. Here’s an example:

Firstly, the javascript:

$(document).ready(function() {
	$("#form").validate({
		rules: {
			username: {
				required: true,
				remote: "/your/url.php"
			}
		},
		messages: {
			username: "Username is required."
		}
	});
});

Pretty standard, nothing out of the ordinary here. Now for the server side response. As I’m sure you’re aware, you can return ‘true’ or ‘false’ however if you want a string, it needs to be formatted as a javascript string:

// /your/url.php
echo '"This username is already taken. Please enter a different username and try again."';

Read More »