js获取时间差值

 function GetTime(firstDate, secondDate) {
     // 1.对事件进行处理
     var firsttime = Date.parse(firstDate + " 00:00:00");
     var secondtime = Date.parse(secondDate + " 00:00:00");
     // 2.获取时间间隔
     var timespan = secondtime - firsttime;
     // 3.获取天
     var day = Math.floor(timespan /  /  /  / );
     // 4.获取小时
     var hour = Math.floor(timespan /  /  / );
     // 5.获取分钟
     var minute = Math.floor(timespan /  /  - hour * );
     // 6.获取秒
     var second = timespan /  - hour *  *  - minute * ;
     return day + "@" + hour + "@" + minute + "@" + second;
 }