对超连接是title属性
对图片是alt或者title属性。title属性比alt属性悠闲，没有title属性的时候显示alt属性的值。
看看这个：
<html>
<body>
<A HREF="#" title="test1">asdfasdf</A>
<BR>
<img src="" title="test2">
<BR>
<img src="" alt="test3">
<BR>
<img src="" title="test4" alt = "asdgasdfsd">
</body>
</html>
对图片是alt或者title属性。title属性比alt属性悠闲，没有title属性的时候显示alt属性的值。
看看这个：
<html>
<body>
<A HREF="#" title="test1">asdfasdf</A>
<BR>
<img src="" title="test2">
<BR>
<img src="" alt="test3">
<BR>
<img src="" title="test4" alt = "asdgasdfsd">
</body>
</html>
<html>
<body>
<A HREF="#" title="test1">asdfasdf</A>
<BR>
<img src="" title="test2">
<BR>
<img src="" alt="test3">
<BR>
<img src="" title="test4" alt = "asdgasdfsd">
<BR>
<span title="test5">asdfasdfg</span>
<BR>
<div title="test6">asdfasdfg</div>
<BR>
<input title="test7">
<BR>
<input type=radio title="test8">
<BR>
<input type=checkbox title="test9">
<BR>
<input type=button title="test10" value="test">
<BR>
<TEXTAREA TITLE="TEST11"></TEXTAREA><BR>
<TABLE title="test12">
<TR>
<TD colspan=2 align=center>asdf</TD>
</TR>
<TR title="test13">
<TD title="test14">asdf</TD>
<TD>asdf</TD>
</TR>
</TABLE></body>
</html>
<html>
<head>
<script Language="JavaScript">
//***********默认设置定义.*********************
tPopWait=50;//停留tWait豪秒后显示提示。
tPopShow=5000;//显示tShow豪秒后关闭提示
showPopStep=20;
popOpacity=99;//***************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: #F8F8F5;color:#000000; border: 1px #000000 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>
</head>
<BODY>
<a href="dispbbs.asp?boardID=6&RootID=56&ID=56" title="我想请问当MOUSE指到网页的图片或是一个超联接上，会自动弹出提示，这个是怎么做的？？<br>作者：xx<br>发表于2002-6-13 20:17:16<br>最后跟贴：呵呵，是这样......">我想请问？</a>
</body>
</html>
http://freehost12.websamba.com/liu752/bbs/index.asp
http://www.csdn.net/expert/topic/802/802480.xml?temp=.8488733 to cxa_2002(颖81)：alt属性应用于AREA,IMG对象，给超链接恐怕不行哦。to possible_Y(因为帅，判了8年！) :
“但是title不能控制显示时间”是什么意思？要求是“当MOUSE指到网页的图片或是一个超联接上”啊，还要控制什么时间？“而且title是属于html的，不是javascript”又是什么意思？