javascript时间戳和日期字符串相互转换

// 获取当前时间戳(以s为单位)
var timestamp = Date.parse(new Date());
timestamp = timestamp / 1000;
//当前时间戳为：1403149534
console.log("当前时间戳为：" + timestamp);

// 获取某个时间格式的时间戳
var stringTime = "2014-07-10 10:21:12";
var timestamp2 = Date.parse(new Date(stringTime));
timestamp2 = timestamp2 / 1000;
//2014-07-10 10:21:12的时间戳为：1404958872 
console.log(stringTime + "的时间戳为：" + timestamp2);

// 将当前时间换成时间格式字符串
var timestamp3 = 1403058804;
var newDate = new Date();
newDate.setTime(timestamp3 * 1000);
// Wed Jun 18 2014 
console.log(newDate.toDateString());
// Wed, 18 Jun 2014 02:33:24 GMT 
console.log(newDate.toGMTString());
// 2014-06-18T02:33:24.000Z
console.log(newDate.toISOString());
// 2014-06-18T02:33:24.000Z 
console.log(newDate.toJSON());
// 2014年6月18日 
console.log(newDate.toLocaleDateString());
// 2014年6月18日 上午10:33:24 
console.log(newDate.toLocaleString());
// 上午10:33:24 
console.log(newDate.toLocaleTimeString());
// Wed Jun 18 2014 10:33:24 GMT+0800 (中国标准时间)
console.log(newDate.toString());
// 10:33:24 GMT+0800 (中国标准时间) 
console.log(newDate.toTimeString());
// Wed, 18 Jun 2014 02:33:24 GMT
console.log(newDate.toUTCString());

Date.prototype.format = function(format) {
       var date = {
              "M+": this.getMonth() + 1,
              "d+": this.getDate(),
              "h+": this.getHours(),
              "m+": this.getMinutes(),
              "s+": this.getSeconds(),
              "q+": Math.floor((this.getMonth() + 3) / 3),
              "S+": this.getMilliseconds()
       };
       if (/(y+)/i.test(format)) {
              format = format.replace(RegExp.$1, (this.getFullYear() + '').substr(4 - RegExp.$1.length));
       }
       for (var k in date) {
              if (new RegExp("(" + k + ")").test(format)) {
                     format = format.replace(RegExp.$1, RegExp.$1.length == 1
                            ? date[k] : ("00" + date[k]).substr(("" + date[k]).length));
              }
       }
       return format;
}
console.log(newDate.format('yyyy-MM-dd h:m:s'));

 

 

/**
 * 获取指定年份的第几周的开始时间戳
 * @param  int year    年份
 * @param  int week 第几周
 * @return int
 */
function getWeek(year,week){
	week = parseInt(week);
	var date1 = new Date(year,0,1);	//1月1号
	var offsetDay = date1.getDay();	//获取星期几	
	var offsetTimestamp  = Date.parse(date1);
	var dayTimestamp = 86400000;	//每天毫秒数
	var firstDayTimestamp = 0;	//第1周的第一天开始时间戳
	if(offsetDay==1){	//周一
		firstDayTimestamp = offsetTimestamp;
	}else{	//非周一
		firstDayTimestamp = offsetTimestamp - dayTimestamp*(7-offsetDay);
	}
	return firstDayTimestamp + (parseInt(week)-1)*7*dayTimestamp;	
}