登录后清除文本框内容

登录后清除文本框内容

<script>
function check(){
setTimeout("clear()",50);
document.form1.submit();
return false
}
function clear(){
document.form1.userid.value="";
document.form1.password.value="";
return false
}
</script>
<form  method="post" action="/boss/login.htm" target="_blank" name="form1">
    <table border="0" cellspacing="0">
     <tr>
      <td height="34" align="right">用户名：</td>
      <td><input name="userid" type="text" size="15"></td>

     </tr>
     <tr>
      <td height="25" align="right">密 码：</td>
      <td><input name="password" type="password" size="15">      </td>

     </tr>
     <tr>
      <td colspan="3" align="center"><input type="button" value="短信群发代理登录" onclick="check()"/></td>
     </tr>
    </table>
</form>