重复提交 禁止连续点击同一链接
?<a href= "http://www.google.com " onclick= "window.open(this.href);document.getElementsByTagName('a')[0].href = 'javascript:void(0)';"> 链接1 </a>
链接disabled =true只显示禁用的效果，但任然可以点<a href="http://www.google.cn" onclick="var that = this; setTimeout(function(){that.href = '###'; that.target=''; that.onclick=function(){ return false; }; });" target="_blank">Open Google in New Window</a>
