小功能JS代码——注册倒计时

<form id="form1" name="form1" method="post" action="">
 <input type="submit" name="Submit" value="同意" />
</form>
<script language="javascript">
document.form1.Submit.disabled = true;
var speed = 1000; //速度
var wait = 10; //停留时间
function updateinfo(){
  if(wait == 0){
    document.form1.Submit.value = "我同意";
    document.form1.Submit.disabled = false;
  }
  else{
    document.form1.Submit.value = "阅读条款"+wait;
    wait--;
    window.setTimeout("updateinfo()",speed);
  }
}
updateinfo();
</script>