alert(GetDateDiff("2018-02-27 19:20:22","2018-02-27 09:20:22","hour"));function GetDateDiff(startTime, endTime, diffType) {  //將xxxx-xx-xx的時間格式，轉換為 xxxx/xx/xx的格式   startTime = startTime.replace(//-/g, "/");  endTime = endTime.replace(//-/g, "/");  //將計算間隔類性字符轉換為小寫  diffType = diffType.toLowerCase();  var sTime =new Date(startTime); //開始時間  var eTime =new Date(endTime); //結束時間  //作為除數的數字  var timeType =1;  switch (diffType) {    case"second":      timeType =1000;    break;    case"minute":      timeType =1000*60;    break;    case"hour":      timeType =1000*3600;    break;    case"day":      timeType =1000*3600*24;    break;    default:    break;  }  return parseInt((eTime.getTime() - sTime.getTime()) / parseInt(timeType));}

var date1=new Date(); //開始時間alert("aa");var date2=new Date();  //結束時間var date3=date2.getTime()-date1.getTime() //時間差的毫秒數//計算出相差天數var days=Math.floor(date3/(24*3600*1000))//計算出小時數var leave1=date3%(24*3600*1000)  //計算天數后剩余的毫秒數var hours=Math.floor(leave1/(3600*1000))//計算相差分鐘數var leave2=leave1%(3600*1000)    //計算小時數后剩余的毫秒數var minutes=Math.floor(leave2/(60*1000))//計算相差秒數var leave3=leave2%(60*1000)   //計算分鐘數后剩余的毫秒數var seconds=Math.round(leave3/1000)alert(" 相差 "+days+"天 "+hours+"小時 "+minutes+" 分鐘"+seconds+" 秒")