<input type="button" value="獲取驗證碼"> 

 input[type=button]  width: 150px;  height: 30px;  background-color: #ff3000;  border: 0;  border-radius: 15px;  color: #fff; } input[type=button].on {  background-color: #eee;  color: #ccc;  cursor: not-allowed; }

 $("input[type='button']").click(btnCheck);  /**  * [btnCheck 按鈕倒計時常用于獲取手機短信驗證碼]  */  function btnCheck() {   $(this).addClass("on");   var time = 5;   $(this).attr("disabled", true);   var timer = setInterval(function() {    if (time == 0) {     clearInterval(timer);     $("input").attr("disabled", false);     $("input").val("獲取驗證碼");     $("input").removeClass("on");    } else {     $('input').val(time + "秒");     time--;    }   }, 1000);  }