摘要：
//自定义扩展$.fn.center = function () { this.css("position","absolute"); this.css("top", ( $(window).height() - this.height() ) / 2+$(window).scrollTop() + "px"); this.css("left", ( $(window).width() - this.width() ) / 2+$(window).scrollLeft() + "px& 阅读全文
