Date.prototype.Format = function (fmt) { //author: meizz
  var o = {
    "M+": this.getMonth() + 1, //月份
    "d+": this.getDate(), //日
    "h+": this.getHours(), //小時(shí)
    "m+": this.getMinutes(), //分
    "s+": this.getSeconds(), //秒
    "q+": Math.floor((this.getMonth() + 3) / 3), //季度
    "S": this.getMilliseconds() //毫秒
  };
  if (/(y+)/.test(fmt)) fmt = fmt.replace(RegExp.$1, (this.getFullYear() + "").substr(4 - RegExp.$1.length));
  for (var k in o)
  if (new RegExp("(" + k + ")").test(fmt)) fmt = fmt.replace(RegExp.$1, (RegExp.$1.length == 1) ? (o[k]) : (("00" + o[k]).substr(("" + o[k]).length)));
  return fmt;
}

<SCRIPT LANGUAGE="JavaScript">
<!--
var myDate = new Date();
  myDate.getYear();    //獲取當(dāng)前年份(2位)
  myDate.getFullYear();  //獲取完整的年份(4位,1970-????)
  myDate.getMonth();   //獲取當(dāng)前月份(0-11,0代表1月)
  myDate.getDate();    //獲取當(dāng)前日(1-31)
  myDate.getDay();    //獲取當(dāng)前星期X(0-6,0代表星期天)
  myDate.getTime();    //獲取當(dāng)前時(shí)間(從1970.1.1開(kāi)始的毫秒數(shù))
  myDate.getHours();   //獲取當(dāng)前小時(shí)數(shù)(0-23)
  myDate.getMinutes();  //獲取當(dāng)前分鐘數(shù)(0-59)
  myDate.getSeconds();  //獲取當(dāng)前秒數(shù)(0-59)
  myDate.getMilliseconds();  //獲取當(dāng)前毫秒數(shù)(0-999)
  myDate.toLocaleDateString();  //獲取當(dāng)前日期
  var mytime=myDate.toLocaleTimeString();  //獲取當(dāng)前時(shí)間
  myDate.toLocaleString( );    //獲取日期與時(shí)間
if (mytime<"23:30:00")
{
alert(mytime);
}
//-->
</SCRIPT>