用javaScript验证登录信息

 
<script type="text/javascript">
    document.getElementById("txtUserName").focus();
    document.getElementById("imgcode").src="vlipage.aspx?t=" + new Date().toString();
    document.oncontextmenu = function(){return false;}
    document.onkeydown = keyEvent;
    function keyEvent()
    {
        if(event.keyCode==13)
        {
            document.getElementById("ImageLogin").click();
        }
    }
    </script>