超链接点击一次就失效不能再点击

如何让超链接点击一次就不能再点呢?

  <a href="<%=path%>/orders/export" class="daoc"  onclick="disAbleA(this,1);return com.whuang.hsj.confirmDelete('确定要导出吗?')"  >导 出(快)</a>&nbsp;
<a href="<%=path%>/orders/exportSlow" class="daoc"  onclick="disAbleA(this,2);return com.whuang.hsj.confirmDelete('确定要导出吗(包含产品详情)?')" >导 出(慢)</a>

 

 var disAbleA=function(object,num){
	if (object!=null) {
		object.onclick=function(){
			return false;
		}
		 function cleanUp22(){
		 	alert("begin");
         if(num==1){
         	object.onclick=function(){
         		return com.whuang.hsj.confirmDelete('确定要导出吗?');
         	}
         }else {
         	object.onclick=function(){
         		return com.whuang.hsj.confirmDelete('确定要导出吗(包含产品详情)?');
         	}
         }
      }
      setTimeout(cleanUp22,4000);
	}
}