momentjs 求小时差异

momentjs  使用

var now1 = moment( moment().unix()*1000);   //获取unix时间戳 需要*1000
var befor_time =  moment(1470040905000)  ;   // 后台接口给的时间戳

//判断小时差
var hour_gap = now1.diff(befor_time,'hours');
if( hour_gap > 12) {
 var day=moment(befor_time).format("YYYY-MM-DD")  ;
 console.log(day)
 }else{
console.log(moment(befor_time).fromNow())
}