date.format，日期格式化
/*
   * date.format
   */
  Date.prototype.format = function (fmt) {
    var o = {
      "M+": this.getMonth() + 1, //月份         
      "d+": this.getDate(), //日         
      "h+": this.getHours() % 12 == 0 ? 12 : this.getHours() % 12, //小时         
      "H+": this.getHours(), //小时         
      "m+": this.getMinutes(), //分         
      "s+": this.getSeconds(), //秒         
      "q+": Math.floor((this.getMonth() + 3) / 3), //季度         
      "S": this.getMilliseconds() //毫秒         
    };
    var week = {
      "0": "/u65e5",
      "1": "/u4e00",
      "2": "/u4e8c",
      "3": "/u4e09",
      "4": "/u56db",
      "5": "/u4e94",
      "6": "/u516d"
    };
    if (/(y+)/.test(fmt)) {
      fmt = fmt.replace(RegExp.$1, (this.getFullYear() + "").substr(4 - RegExp.$1.length));
    }
    if (/(E+)/.test(fmt)) {
      fmt = fmt.replace(RegExp.$1, ((RegExp.$1.length > 1) ? (RegExp.$1.length > 2 ? "/u661f/u671f" : "/u5468") : "") + week[this.getDay() + ""]);
    }
    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;
  }
  //window.alert(date.format("yyyy-MM-dd EEE hh:mm:ss"));