2.1 短时间，形如 (13:04:06)
      function isTime(str)
      {
        var a = str.match(/^(\d{1,2})(:)?(\d{1,2})\2(\d{1,2})$/);
        if (a == null) {alert('输入的参数不是时间格式'); return false;}
        if (a[1]>24 || a[3]>60 || a[4]>60)
        {
          alert("时间格式不对");
          return false
        }
        return true;
      }
  2.2 短日期，形如 (2003-12-05)
      function strDateTime(str)
      {
         var r = str.match(/^(\d{1,4})(-|\/)(\d{1,2})\2(\d{1,2})$/);
         if(r==null)return false;
         var d= new Date(r[1], r[3]-1, r[4]);
         return (d.getFullYear()==r[1]&&(d.getMonth()+1)==r[3]&&d.getDate()==r[4]);
      }
  2.3 长时间，形如 (2003-12-05 13:04:06)
      function strDateTime(str)
      {
        var reg = /^(\d{1,4})(-|\/)(\d{1,2})\2(\d{1,2}) (\d{1,2}):(\d{1,2}):(\d{1,2})$/;
        var r = str.match(reg);
        if(r==null)return false;
        var d= new Date(r[1], r[3]-1,r[4],r[5],r[6],r[7]);
        return (d.getFullYear()==r[1]&&(d.getMonth()+1)==r[3]&&d.getDate()==r[4]&&d.getHours()==r[5]&&d.getMinutes()==r[6]&&d.getSeconds()==r[7]);
      }