滚动条事件,当页面滚动到距顶部一定高度时某DIV自动隐藏和显示

$(function () {              

            //绑定滚动条事件  

              //绑定滚动条事件  

            $(window).bind("scroll", function () {  

                var sTop = $(window).scrollTop();  

                var sTop = parseInt(sTop);  

                if (sTop >= 130) {  

                    if (!$("#scrollSearchDiv").is(":visible")) {  

                        try {  

                            $("#scrollSearchDiv").slideDown();  

                        } catch (e) {  

                            $("#scrollSearchDiv").show();  

                        }                        

                    }  

                }  

                else {  

                    if ($("#scrollSearchDiv").is(":visible")) {  

                        try {  

                            $("#scrollSearchDiv").slideUp();  

                        } catch (e) {  

                            $("#scrollSearchDiv").hide();  

                        }                         

                    }  

                }   

            });  

        })