/*
双击滚动，单击停止滚动
例如：$().myp2cDblScroll({time:50,step:2});
* Copyright (c) 2008 chinaxiaofei@mypc.com
*/
(function ($) {
    $.fn.myp2cDblScroll = function (options) {
        var defaults = { time: 50, step: 2 };
        var c = $.extend({}, defaults, options);
        //
        var $w = $(window);
        //
        var loop = true;
        function scroll() {
            var top = $w.scrollTop() + c.step;
            $w.scrollTop(top);
            if (loop) {
                if (top == $w.scrollTop()) {
                    setTimeout(scroll, c.time);
                }
                else {
                    loop = false;
                }
            }
        };
        //
        $(document.body).dblclick(function () {
            loop = true;
            scroll();
        }).click(function () {
            loop = false;
        });
        //
        return this;
    };
})(jQuery);

//自动按默认方式执行
$().myp2cDblScroll();