按钮变灰倒计时复原

    
         <script type="text/javascript">

              function timer(){

                var timer=document.getElementById("test");
                     timer.disabled=true;
                  
          window.setTimeout("recovery();",3000);


                }
            
               function recovery(){

                   var timer=document.getElementById("test");
                     timer.disabled=false;
                     timer.value="一分钟如没有收到，请重新点击";

               }
     

         &lt;/script&gt;<input type="button" id="test" value="发送到手机">