日期:2014-05-16 浏览次数:20406 次
var top_height = document.getElementById("top").offsetHeight;
var left_height = document.getElementById("left").offsetHeight;
 $(document).ready(function() {
            $(document).scroll(function() {
                var scroll_top = document.documentElement.scrollTop;
                var left_top = $("#left").offset().top;
                var m2_top = $("#m2").offset().top;
                if ((scroll_top > top_height) && (scroll_top + left_height < m2_top)) {
                    $("#left").css({ "top": scroll_top });
                }
                else {
                    if (scroll_top < top_height) {
                        $("#left").css({ "top": top_height + 20 });
                    }
                    else {
                        $("#left").css({ "top": m2_top - 10 - left_height });
                    }
                }
            })
        })