//分钟

                   let timeM= parseInt(msg/1000/60%60);

                   if(timeM<10){

                      timeM="0"+timeM;

                       }

                   //秒钟

                   let timeS=parseInt(msg/1000%60);

                   if(timeS<10){

                       timeS="0"+timeS;

                        }

                  let time=timeM+":"+timeS;