js时间戳转换日期

//js时间戳转换日期
function formatDate(now) {
 var year=now.getFullYear();
 var month=now.getMonth()+1;
 var date=now.getDate();
 var hour=now.getHours();
 var minute=now.getMinutes();
 var second=now.getSeconds();
 return year+"-"+month+"-"+date+" "+hour+":"+minute+":"+second;
}

var d=new Date(时间戳（毫秒）);
alert(formatDate(d));