JavaScript按回车登录处理

<script>   if (document.addEventListener) {//如果是Firefox        document.addEventListener("keypress", fireFoxHandler, true);   } else {    document.attachEvent("onkeypress", ieHandler);   }   function fireFoxHandler(evt) {    //alert("firefox");        if (evt.keyCode == 13) {     loginSubmit();    }   }   function ieHandler(evt) {    //alert("IE");        if (evt.keyCode == 13) {     loginSubmit();    }   }  </script>