jquery-numeric.js

/*!
 * Numeric.js Jquery extension v0.1.0
 * https://github.com/lcavadas/jquery-numeric
 *
 * Copyright 2012, Luís Serralheiro
 */
(function ($) {
    $.fn.numeric = function (opt) {

        var that = this;
        var opts = {max: Number(this.attr('max')), min: Number(this.attr('min')), decimal: true};
        $.extend(opts, opt);

        var currentNumber;

        this.bind('keypress paste drop', function (e) {
            currentNumber = that.val();

            var validate = function (numberToValidate, defaultNumber) {
                if (!isNaN(numberToValidate) && numberToValidate <= opts.max && numberToValidate >= opts.min) {
                    that.val(opts.decimal ? numberToValidate : Number(numberToValidate).toFixed(0));
                } else {
                    if (that.val() !== '-') {
                        that.val(defaultNumber);
                    }
                }
            };

            window.setTimeout(function () {
                validate(that.val(), currentNumber);
            }, 1);
        });
    };
}(jQuery));