鼠标跟随提示框

鼠标移入某区域中鼠标右下角显示提示信息：

$(document).ready(function(){
    // 创建一个div显示提示信息
    var dropTitle = document.createElement("div");
    dropTitle.id= "backdropTitle";
    dropTitle.style.backgroundColor="#fff";
    dropTitle.innerHTML="提示信息";
    document.getElementsByTagName('body')[0].appendChild(dropTitle);

    // 鼠标移入遮罩层事件
    var backdropTitle = document.getElementById("backdropTitle");
    var backdropBorderS = document.getElementsByClassName("backdrop-border");
    backdropTitle.style.display = "none";
    for(var i=0,len=backdropBorderS.length;i<len;i++){
        backdropBorderS[i].onmousemove = function(evt) {
            var oEvent = evt || window.event;
            var scrollleft = document.documentElement.scrollLeft || document.body.scrollLeft;
            var scrolltop = document.documentElement.scrollTop || document.body.scrollTop;
            backdropTitle.style.display = "block";
            backdropTitle.style.position = "absolute";
            backdropTitle.style.left = oEvent.clientX + scrollleft + 10 + "px";
            backdropTitle.style.top = oEvent.clientY + scrolltop + 10 + "px";
            backdropTitle.style.zIndex = "2060";
            setTimeout(function(){
                backdropTitle.style.display = "none";
            },6000);
        };
        backdropBorderS[i].onmouseout = function (){
            backdropTitle.style.display = "none";
        }
    }
});