js 获取日期时间段

/**
 * DateUtil.js 日期工具包 时间:2011-02-12 注：1天=86400000毫秒 邮箱：[e-mail]
 */
function DateUtil() {
	this.WeekDay;// 星期几
	this.WeekDayStr;
	this.Day;// 当天
	this.Year;// 当年
	this.Month;// 当月
	this.Hours;// 当前小时
	this.Minutes;
	this.Seconds;
	this.Time;// 当前事件
	var Nowdate = new Date();
	this.WeekDay = Nowdate.getDay();
	this.Month = Nowdate.getMonth();
	this.Day = Nowdate.getDate();
	this.Year = Nowdate.getFullYear();
	this.WeekDayStr = '星期' + '日一二三四五六'.charAt(this.WeekDay)
	this.Hours = Nowdate.getHours();
	this.Minutes = Nowdate.getMinutes();
	this.Seconds = Nowdate.getSeconds();
	this.Time = this.Year + "-" + (this.Month + 1) + "-" + this.Day + " "
			+ this.Hours + ":" + this.Minutes + ":" + this.Seconds;

	// 今天
	this.showCurrentDay = function() {
		return Nowdate;
	};
	// 本周第一天
	this.showWeekFirstDay = function() {
		var WeekFirstDay = new Date(Nowdate - (this.WeekDay - 1) * 86400000);
		return WeekFirstDay;
	};
	// 本周最后一天
	this.showWeekLastDay = function() {
		var WeekFirstDay = this.showWeekFirstDay();
		var WeekLastDay = new Date((WeekFirstDay / 1000 + 6 * 86400) * 1000);
		return WeekLastDay;
	};
	// 本月第一天
	this.showMonthFirstDay = function() {
		var MonthFirstDay = new Date(this.Year, this.Month, 1);
		return MonthFirstDay;
	};
	// 本月最后一天
	this.showMonthLastDay = function() {
		var MonthNextFirstDay = new Date(this.Year, this.Month + 1, 1);
		var MonthLastDay = new Date(MonthNextFirstDay - 86400000);
		return MonthLastDay;
	};

	// 当年第一天
	this.showYearFirstDay = function() {
		var YearFirstDay = new Date(this.Year, 0, 1);
		return YearFirstDay;
	};
	// 当年最后一天
	this.showYearLastDay = function() {
		var YearNextFirstDay = new Date(this.Year + 1, 0, 1);
		var YearLastDay = new Date(YearNextFirstDay - 86400000);
		return YearLastDay;
	};

	// 上年第一天
	this.showYearPreviousFirstDay = function() {
		var YearPreviousFirstDay = new Date(this.Year - 1, 0, 1);
		return YearPreviousFirstDay;
	};
	// 上年最后一天
	this.showYearPreviousLastDay = function() {
		var YearFirstDay = this.showYearFirstDay();
		var YearPreviousLastDay = new Date(YearFirstDay - 86400000);
		return YearPreviousLastDay;
	};

	// 下年第一天
	this.showYearNextFirstDay = function() {
		var YearNextFirstDay = new Date(this.Year + 1, 0, 1);
		return YearNextFirstDay;
	};
	// 下年最后一天
	this.showYearNextLastDay = function() {
		var step = new Date(this.Year + 2, 0, 1);
		var YearNextLastDay = new Date(step - 86400000);
		return YearNextLastDay;
	};

	// 上月第一天
	this.showPreviousFirstDay = function() {
		var MonthFirstDay = this.showMonthFirstDay()
		return new Date(MonthFirstDay.getFullYear(), MonthFirstDay.getMonth()
						- 1, 1)
	};
	// 上月最后一天
	this.showPreviousLastDay = function() {
		var MonthFirstDay = this.showMonthFirstDay();
		return new Date(MonthFirstDay - 86400000);
	};
	// 上周第一天
	this.showPreviousFirstWeekDay = function() {
		var WeekFirstDay = this.showWeekFirstDay()
		return new Date(WeekFirstDay - 86400000 * 7)
	};
	// 上周最后一天
	this.showPreviousLastWeekDay = function() {
		var WeekFirstDay = this.showWeekFirstDay()
		return new Date(WeekFirstDay - 86400000)
	};
	// 上一天
	this.showPreviousDay = function() {
		var MonthFirstDay = new Date();
		return new Date(MonthFirstDay - 86400000);
	};
	// 下一天
	this.showNextDay = function() {
		var MonthFirstDay = new Date();
		return new Date((MonthFirstDay / 1000 + 86400) * 1000);
	};
	// 下周第一天
	this.showNextFirstWeekDay = function() {
		var MonthFirstDay = this.showWeekLastDay()
		return new Date((MonthFirstDay / 1000 + 86400) * 1000)
	};
	// 下周最后一天
	this.showNextLastWeekDay = function() {
		var MonthFirstDay = this.showWeekLastDay()
		return new Date((MonthFirstDay / 1000 + 7 * 86400) * 1000)
	};
	// 下月第一天
	this.showNextFirstDay = function() {
		var MonthFirstDay = this.showMonthFirstDay()
		return new Date(MonthFirstDay.getFullYear(), MonthFirstDay.getMonth()
						+ 1, 1)
	};
	// 下月最后一天
	this.showNextLastDay = function() {
		var MonthFirstDay = this.showMonthFirstDay()
		return new Date(new Date(MonthFirstDay.getFullYear(), MonthFirstDay
						.getMonth()
						+ 2, 1)
				- 86400000)
	};

	// 返回json
	this.toObject = function(startTime, endTime) {
		var obj = {
			start : startTime.getFullYear() + "-" + (startTime.getMonth() + 1)
					+ "-" + startTime.getDate(),
			end : endTime.getFullYear() + "-" + (endTime.getMonth() + 1) + "-"
					+ endTime.getDate()
		};
		return obj;
	}
};
// 上一年 {start:2010-01-01 00:00:00,end:2010-12-31 23:59:59}
DateUtil.prototype.PreviousYear = function() {
	return this.toObject(this.showYearPreviousFirstDay(), this
					.showYearPreviousLastDay());
};
// 本年 {start:2011-01-01 00:00:00,end:2011-12-31 23:59:59}
DateUtil.prototype.CurrentYear = function() {
	return this.toObject(this.showYearFirstDay(), this.showYearLastDay());
};
// 下一年 {start:2012-01-01 00:00:00,end:2012-12-31 23:59:59}
DateUtil.prototype.NextYear = function() {
	return this.toObject(this.showYearNextFirstDay(), this
					.showYearNextLastDay());
};
// 上一月 {start:2011-01-01 00:00:00,end:2011-01-31 23:59:59}
DateUtil.prototype.PreviousMonth = function() {
	return this.toObject(this.showPreviousFirstDay(), this
					.showPreviousLastDay());
};
// 本月 {start:2011-02-01 00:00:00,end:2011-02-28 23:59:59}
DateUtil.prototype.CurrentMonth = function() {
	return this.toObject(this.showMonthFirstDay(), this.showMonthLastDay());
};
// 下一月 {start:2011-03-01 00:00:00,end:2011-03-31 23:59:59}
DateUtil.prototype.NextMonth = function() {
	return this.toObject(this.showNextFirstDay(), this.showNextLastDay());
};
// 上一周
DateUtil.prototype.PreviousWeekDay = function() {
	return this.toObject(this.showPreviousFirstWeekDay(), this
					.showPreviousLastWeekDay());
};
// 本周
DateUtil.prototype.CurrentWeekDay = function() {
	return this.toObject(this.showWeekFirstDay(), this.showWeekLastDay());
};
// 下一周
DateUtil.prototype.NextWeekDay = function() {
	return this.toObject(this.showNextFirstWeekDay(), this
					.showNextLastWeekDay());
};
// 上一天
DateUtil.prototype.PreviousDay = function() {
	return this.toObject(this.showPreviousDay(), this.showPreviousDay());
};
// 今天
DateUtil.prototype.CurrentDay = function() {
	return this.toObject(this.showCurrentDay(), this.showCurrentDay());
};
// 下一天
DateUtil.prototype.NextDay = function() {
	return this.toObject(this.showNextDay(), this.showNextDay());
};