//获取当前的前几天时间 type 1 前一天 
// add 为1时是未来几天 ，0时是前几天
//nowdate 传人时间
 function  getdatetime(nowdate,type,add){
	 // console.log('date',type)  
	var date = new Date()
	if(nowdate){
		if(add==1){
			date = new Date(new Date(nowdate).getTime()*1 + type*24*3600*1000);
		}else{
			date = new Date(new Date(nowdate).getTime()-type*24*3600*1000);
		}
	}
	
	
	// console.log('date',date)  
	var up = "-";
	var up1 = ":";
	var month = date.getMonth() + 1<10? "0"+(date.getMonth() + 1):date.getMonth() + 1;
	var strDate = date.getDate()<10? "0" + date.getDate():date.getDate();
	var getHours=date.getHours()<10?"0" +date.getHours(): date.getHours();
	var getMinutes=date.getMinutes()<10?"0" +date.getMinutes(): date.getMinutes();
	var getSeconds=date.getSeconds()<10?"0" +date.getSeconds(): date.getSeconds();
	var currentdate = date.getFullYear() + up  + month  + up  + strDate + " "  + getHours  + up1  + getMinutes + up1 + getSeconds;
	return currentdate;
}