css样式：
.tooltip { border:1px solid #f00; }
javascript：
function initevent() { var div2 = document.getElementById("div2"); var links = div2.getElementsByTagName("a"); for (var i = 0; i < links.length; i++) { var link = links[i]; link.onmouseover = function () { var dive = document.createElement("div"); dive.style.position = "absolute"; dive.className = "tooltip"; dive.style.left = window.event.clientX; dive.style.top = window.event.clientY; dive.innerText = "这是一个好网站"; document.body.appendChild(dive); }; link.onmouseout = function () { var divs = document.getElementsByTagName("div"); for (var i = 0; i < divs.length; i++) { var div = divs[i]; if (div.className == "tooltip") { document.body.removeChild(div); //消除掉 //div.style.display = "none";//隐藏掉，占用内存 } } }; } } </script>
网页内容：
<body οnlοad="initevent()"> <div id="div2"> <p><a href="http://www.baidu.com" mce_href="http://www.baidu.com">百度</a></p> <p><a href="http://www.baidu.com" mce_href="http://www.baidu.com">新浪</a></p> <p><a href="http://www.baidu.com" mce_href="http://www.baidu.com">搜狐</a></p> </div> </body>
