bootstrapvalidator/src/js/validator/hexColor.js

The best jQuery plugin to validate form fields. Designed to use with Bootstrap 3

(function($) {
    $.fn.bootstrapValidator.i18n.hexColor = $.extend($.fn.bootstrapValidator.i18n.hexColor || {}, {
        'default': 'Please enter a valid hex color'
    });

    $.fn.bootstrapValidator.validators.hexColor = {
        enableByHtml5: function($field) {
            return ('color' === $field.attr('type'));
        },

        /**
         * Return true if the input value is a valid hex color
         *
         * @param {BootstrapValidator} validator The validator plugin instance
         * @param {jQuery} $field Field element
         * @param {Object} options Can consist of the following keys:
         * - message: The invalid message
         * @returns {Boolean}
         */
        validate: function(validator, $field, options) {
            var value = $field.val();
            if (value === '') {
                return true;
            }

            return ('color' === $field.attr('type'))
                        // Only accept 6 hex character values due to the HTML 5 spec
                        // See http://www.w3.org/TR/html-markup/input.color.html#input.color.attrs.value
                        ? /^#[0-9A-F]{6}$/i.test(value)
                        : /(^#[0-9A-F]{6}$)|(^#[0-9A-F]{3}$)/i.test(value);
        }
    };
}(window.jQuery));