简单实现js浮动框

<!-- 浮动窗口样式css begin --><style type="text/css">#msg_win {  border: 1px solid #A67901;  background: #EAEAEA;  width: 240px;  position: absolute;  right: 0;  font-size: 12px;  font-family: Arial;  margin: 0px;  display: none;  overflow: hidden;  z-index: 99;}#msg_win .icos {  position: absolute;  top: 2px;  *top: 0px;  right: 2px;  z-index: 9;}.icos a {  float: left;  color: #833B02;  margin: 1px;  text-align: center;  font-weight: bold;  width: 14px;  height: 22px;  line-height: 22px;  padding: 1px;  text-decoration: none;  font-family: webdings;}.icos a:hover {  color: #fff;}#msg_title {  background: #BBDEF6;  border-bottom: 1px solid #A67901;  border-top: 1px solid #FFF;  border-left: 1px solid #FFF;  color: #000;  height: 25px;  line-height: 25px;  text-indent: 5px;}#msg_content {  margin: 5px;  margin-right: 0;  width: 230px;  height: 126px;  overflow: hidden;}</style><!-- 浮动窗口样式css end -->

<!-- 浮动窗口js，必须要放置到最后 begin--><script type="text/javascript">var Message={  set: function() {//最小化与恢复状态切换    var set=this.minbtn.status == 1?[0,1,'block',this.char[0],'最小化']:[1,0,'none',this.char[1],'展开'];    this.minbtn.status=set[0];    this.win.style.borderBottomWidth=set[1];    this.content.style.display =set[2];    this.minbtn.innerHTML =set[3]    this.minbtn.title = set[4];    this.win.style.top = this.getY().top;  },  close: function() {//关闭    this.win.style.display = 'none';    window.onscroll = null;  },  setOpacity: function(x) {//设置透明度    var v = x >= 100 ? '': 'Alpha(opacity=' + x + ')';    this.win.style.visibility = x<=0?'hidden':'visible';//IE有绝对或相对定位内容不随父透明度变化的bug    this.win.style.filter = v;    this.win.style.opacity = x / 100;  },  show: function() {//渐显    clearInterval(this.timer2);    var me = this,fx = this.fx(0, 100, 0.1),t = 0;    this.timer2 = setInterval(function() {      t = fx();      me.setOpacity(t[0]);      if (t[1] == 0) {clearInterval(me.timer2) }    },10);  },  fx: function(a, b, c) {//缓冲计算    var cMath = Math[(a - b) > 0 ? "floor": "ceil"],c = c || 0.1;    return function() {return [a += cMath((b - a) * c), a - b]}  },  getY: function() {//计算移动坐标    var d = document,b = document.body, e = document.documentElement;    var s = Math.max(b.scrollTop, e.scrollTop);    var h = /BackCompat/i.test(document.compatMode)?b.clientHeight:e.clientHeight;    var h2 = this.win.offsetHeight;    return {foot: s + h + h2 + 2+'px',top: s + h - h2 - 2+'px'}  },  moveTo: function(y) {//移动动画    clearInterval(this.timer);    var me = this,a = parseInt(this.win.style.top)||0;    var fx = this.fx(a, parseInt(y));    var t = 0 ;    this.timer = setInterval(function() {      t = fx();      me.win.style.top = t[0]+'px';      if (t[1] == 0) {        clearInterval(me.timer);        me.bind();      }    },10);  },  bind:function (){//绑定窗口滚动条与大小变化事件    var me=this,st,rt;    window.onscroll = function() {      clearTimeout(st);      clearTimeout(me.timer2);      me.setOpacity(0);      st = setTimeout(function() {      me.win.style.top = me.getY().top;      me.show();      },600);    };    window.onresize = function (){      clearTimeout(rt);      rt = setTimeout(function() {me.win.style.top = me.getY().top},100);    }  },  init: function() {//创建HTML    function $(id) {return document.getElementById(id)};    this.win=$('msg_win');    var set={minbtn: 'msg_min',closebtn: 'msg_close',title: 'msg_title',content: 'msg_content'};    for (var Id in set) {this[Id] = $(set[Id])};    var me = this;    this.minbtn.onclick = function() {me.set();this.blur()};    this.closebtn.onclick = function() {me.close()};    this.char=navigator.userAgent.toLowerCase().indexOf('firefox')+1?['_','::','×']:['0','2','r'];//FF不支持webdings字体    this.minbtn.innerHTML=this.char[0];    this.closebtn.innerHTML=this.char[2];    setTimeout(function() {//初始化最先位置      me.win.style.display = 'block';      me.win.style.top = me.getY().foot;      me.moveTo(me.getY().top);    },0);    return this;  }};Message.init();</script><!-- 浮动窗口js end-->

<!-- 浮动窗口html代码 begin --><hr><div id="msg_win" style="display: block; top: 490px; visibility: visible; opacity: 1;"> <div class="icos">  <a id="msg_min" title="最小化" href="javascript:void 0">_</a><a id="msg_close" title="关闭" href="javascript:void 0">×</a> </div> <div id="msg_title">设备运行情况--></div> <div id="msg_content" style="overflow: auto; height: 150px; width: 100%; white-space: nowrap">  ${commonMsg.devRun }  </div></div><!-- 浮动窗口html代码 end -->