List adding timer (positive and countdown)

   
   //  To obtain a list of 
   onload() {
      getList().then(res => {
        this.tableData = res.data.data.records;
        
        //  timer 
        this.tableData.forEach(el=>{
           el.excessTime = Date.now(); //  Initial time value 
          this.isTimingcheng(el); //  Each mount timer 
        })
      });
    }



   //  timer 
   isTimingcheng(row) {
      if ( Judge when the condition clears the timer ) {
        row.countDown = setInterval(() => {
          row.excessTime = row.excessTime + 1000;
          this.$forceUpdate(); //  Refresh every update dom
        }, 1000);
      } else {
        clearInterval(row.countDown); //  Clear timer 
      }
    }



   //  Clear all timers 
   clearAll(list){
     list.forEach(el=>{
       clearInterval(el.countDown)
     })
   }

Each row of the list has its own timing ！！！