JQuery style with !important

styleextension.js

(function($) {
    if ($.fn.style) {
        return;
    }

    // Escape regex chars with \
    var escape = function(text) {
        return text.replace(/[-[\]{}()*+?.,\\^$|#\s]/g, "\\$&");
    };

    // For those who need them (< IE 9), add support for CSS functions
    var isStyleFuncSupported = !!CSSStyleDeclaration.prototype.getPropertyValue;
    if (!isStyleFuncSupported) {
        CSSStyleDeclaration.prototype.getPropertyValue = function(a) {
            return this.getAttribute(a);
        };
        CSSStyleDeclaration.prototype.setProperty = function(styleName, value, priority) {
            this.setAttribute(styleName, value);
            var priority = typeof priority != 'undefined' ? priority : '';
            if (priority != '') {
                // Add priority manually
                var rule = new RegExp(escape(styleName) + '\\s*:\\s*' + escape(value) +
                    '(\\s*;)?', 'gmi');
                this.cssText =
                    this.cssText.replace(rule, styleName + ': ' + value + ' !' + priority + ';');
            }
        };
        CSSStyleDeclaration.prototype.removeProperty = function(a) {
            return this.removeAttribute(a);
        };
        CSSStyleDeclaration.prototype.getPropertyPriority = function(styleName) {
            var rule = new RegExp(escape(styleName) + '\\s*:\\s*[^\\s]*\\s*!important(\\s*;)?',
                'gmi');
            return rule.test(this.cssText) ? 'important' : '';
        }
    }

    // The style function
    $.fn.style = function(styleName, value, priority) {
        // DOM node
        var node = this.get(0);
        // Ensure we have a DOM node
        if (typeof node == 'undefined') {
            return this;
        }
        // CSSStyleDeclaration
        var style = this.get(0).style;
        // Getter/Setter
        if (typeof styleName != 'undefined') {
            if (typeof value != 'undefined') {
                // Set style property
                priority = typeof priority != 'undefined' ? priority : '';
                style.setProperty(styleName, value, priority);
                return this;
            } else {
                // Get style property
                return style.getPropertyValue(styleName);
            }
        } else {
            // Get CSSStyleDeclaration
            return style;
        }
    };
})(jQuery);

Use = $(this).style('color','red','important')