var countdown=60; function sendemail(){ var obj = $("#btn"); settime(obj); } function settime(obj) { //傳送驗證碼倒計時 if (countdown == 0) { obj.attr('disabled',false); //obj.removeattr("disabled"); obj.val("免費獲取驗證碼"); countdown = 60; return; } else { obj.attr('disabled',true); obj.val("重新發送(" + countdown + ")"); countdown--; } setTimeout(function() { settime(obj) } ,1000) }