JS獲取上月，本月，下月的開始時間與結束時間

``###JS獲取上月，本月，下月的開始時間與結束時間(記錄)

//獲取當天的時間
function getToday() { 
	var date = new Date();
	return date .getFullYear() + "-" + (date .getMonth()+1) + "-" +  date .getDate() ;
}


/** 
* 獲得相對當前周AddWeekCount個周的起止日期 
* AddWeekCount為0代表當前周  為-1代表上一個周  為1代表下一個周以此類推
* **/ 
function getWeekStartAndEnd(AddWeekCount) { 
//起止日期數組  
	var startStop = new Array(); 
	//一天的毫秒數  
	var millisecond = 1000 * 60 * 60 * 24; 
	//獲取當前時間  
	var currentDate = new Date();
	//相對於當前日期AddWeekCount個周的日期
	currentDate = new Date(currentDate.getTime() + (millisecond * 7*AddWeekCount));
	//返回date是一周中的某一天
	var week = currentDate.getDay(); 
	//返回date是一個月中的某一天  
	var month = currentDate.getDate();
	//減去的天數  
	var minusDay = week != 0 ? week - 1 : 6; 
	//獲得當前周的第一天  
	var currentWeekFirstDay = new Date(currentDate.getTime() - (millisecond * minusDay)); 
	//獲得當前周的最后一天
	 var currentWeekLastDay = new Date(currentWeekFirstDay.getTime() + (millisecond * 6));
	//添加至數組  
	startStop.push(getDateStr3(currentWeekFirstDay)); 
	startStop.push(getDateStr3(currentWeekLastDay)); 
	
	return startStop; 
} 
/** 
* 獲得相對當月AddMonthCount個月的起止日期 
* AddMonthCount為0 代表當月 為-1代表上一個月 為1代表下一個月 以此類推
* ***/ 
function getMonthStartAndEnd(AddMonthCount) { 
	//起止日期數組  
	var startStop = new Array(); 
	//獲取當前時間  
	var currentDate = new Date();
	var month=currentDate.getMonth()+AddMonthCount;
	if(month<0){
	  var n = parseInt((-month)/12);
	  month += n*12;
	  currentDate.setFullYear(currentDate.getFullYear()-n);
	}
	currentDate = new Date(currentDate.setMonth(month));
	//獲得當前月份0-11  
	var currentMonth = currentDate.getMonth(); 
	//獲得當前年份4位年  
	var currentYear = currentDate.getFullYear(); 
	//獲得上一個月的第一天  
	var currentMonthFirstDay = new Date(currentYear, currentMonth,1); 
	//獲得上一月的最后一天  
	var currentMonthLastDay = new Date(currentYear, currentMonth+1, 0); 
	//添加至數組  
	startStop.push(getDateStr3(currentMonthFirstDay)); 
	startStop.push(getDateStr3(currentMonthLastDay)); 
	//返回  
	return startStop; 
}


//獲取當前日期yy-mm-dd
//date 為時間對象
function getDateStr3(date) {
	var year = "";
	var month = "";
	var day = "";
	var now = date;
	year = ""+now.getFullYear();
	if((now.getMonth()+1)<10){
	  month = "0"+(now.getMonth()+1);
	}else{
	  month = ""+(now.getMonth()+1);
	}
	if((now.getDate())<10){
	  day = "0"+(now.getDate());
	}else{
	  day = ""+(now.getDate());
	}
	return year+"-"+month+"-"+day;
}