js一个非常好的Tooltip代码

<script language=javascript>
<!--
//***********默认设置定义.*********************
tPopWait=1;    //停留tWait豪秒后显示提示。
tPopShow=6000;    //显示tShow豪秒后关闭提示
showPopStep=20;
popOpacity=95;
fontcolor="#333333";
bgcolor="#f7f7f7";
bordercolor="#000000";

//***************内部变量定义*****************
sPop=null;
curShow=null;
tFadeOut=null;
tFadeIn=null;
tFadeWaiting=null;

document.write("<style type='text/css'id='defaultPopStyle'>");
document.write(".cPopText {  background-color: " + bgcolor + ";color:" + fontcolor + "; border: 1px " + bordercolor + " solid;font-color: font-size: 12px; padding-right: 4px; padding-left: 4px; height: 20px; padding-top: 2px; padding-bottom: 2px; filter: Alpha(Opacity=0)}");
document.write("</style>");
document.write("<div id='dypopLayer' style='position:absolute;z-index:1000;' class='cPopText'></div>");

function showPopupText(){
var o=event.srcElement;
  MouseX=event.x;
  MouseY=event.y;
  if(o.alt!=null && o.alt!=""){o.dypop=o.alt;o.alt=""};
       if(o.title!=null && o.title!=""){o.dypop=o.title;o.title=""};
  if(o.dypop!=sPop) {
      sPop=o.dypop;
      clearTimeout(curShow);
      clearTimeout(tFadeOut);
      clearTimeout(tFadeIn);
      clearTimeout(tFadeWaiting); 
      if(sPop==null || sPop=="") {
        dypopLayer.innerHTML="";
        dypopLayer.style.filter="Alpha()";
        dypopLayer.filters.Alpha.opacity=0; 
        }
      else {
        if(o.dyclass!=null) popStyle=o.dyclass
          else popStyle="cPopText";
        curShow=setTimeout("showIt()",tPopWait);
      }
     
  }
}

function showIt(){
    dypopLayer.className=popStyle;
    dypopLayer.innerHTML=sPop;
    popWidth=dypopLayer.clientWidth;
    popHeight=dypopLayer.clientHeight;
    if(MouseX+12+popWidth>document.body.clientWidth) popLeftAdjust=-popWidth-24
      else popLeftAdjust=0;
    if(MouseY+12+popHeight>document.body.clientHeight) popTopAdjust=-popHeight-24
      else popTopAdjust=0;
    dypopLayer.style.left=MouseX+12+document.body.scrollLeft+popLeftAdjust;
    dypopLayer.style.top=MouseY+12+document.body.scrollTop+popTopAdjust;
    dypopLayer.style.filter="Alpha(Opacity=0)";
    fadeOut();
}

function fadeOut(){
  if(dypopLayer.filters.Alpha.opacity<popOpacity) {
    dypopLayer.filters.Alpha.opacity+=showPopStep;
    tFadeOut=setTimeout("fadeOut()",1);
    }
    else {
      dypopLayer.filters.Alpha.opacity=popOpacity;
      tFadeWaiting=setTimeout("fadeIn()",tPopShow);
      }
}

function fadeIn(){
  if(dypopLayer.filters.Alpha.opacity>0) {
    dypopLayer.filters.Alpha.opacity-=1;
    tFadeIn=setTimeout("fadeIn()",1);
    }
}
document.onmouseover=showPopupText;
-->
</script>

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