<script type="text/javascript">
function submitByEnter()
{
if(event.keyCode == 13)
{
login();
document.getElementByIdx_x("password").value="";
}
}
</script>
<form class="mainmenu" onkeydown="submitByEnter();">
原文：http://www.cnblogs.com/start-fxw/p/4561749.html