js获取当前时间和获取前N天 格式：yyyy-MM-dd HH:mm:ss

1.获取当前时间：

function getNowFormatDate() {
		    var date = new Date();
		    var seperator1 = "-";
		    var seperator2 = ":";
		    var year = date.getFullYear();
		    var month = date.getMonth() + 1;
		    var strDate = date.getDate();
		    if (month >= 1 && month <= 9) {
		        month = "0" + month;
		    }
		    if (strDate >= 0 && strDate <= 9) {
		        strDate = "0" + strDate;
		    }
		    var currentdate = year + seperator1 + month + seperator1 + strDate
		            + " " + date.getHours() + seperator2 + date.getMinutes()
		            + seperator2 + date.getSeconds();
		    return currentdate;
		}function getNowFormatDate() {