<a href="http://www.google.cn" onclick="return myclick();">链接到谷歌</a><script type="text/javascript"> function myclick(){ alert('呵呵，我失效了吗？'); return false; }</script>
<a href="http://www.sina.com" id="mylink">连接</a> <input type=button value="dian" ID=Button1 onclick="document.links('mylink').outerHTML='连接';"><a href="http://www.sina.com" id="mylink">连接</a> <input type=button value="dian" ID=Button1 onclick="document.links('mylink').disabled=!document.links('mylink').disabled;">
