highCharts提示框中显示当前时间的方法

shared: true,//当提示框被共享时，整个绘图区都将捕捉鼠标指针的移动。提示框文本显示有序数据（不包括饼图，散点图和标志图等）的系列类型将被显示在同一个提示框中。    formatter : function() {//提示框内容格式化回调函数，返回 false 可以针对某个点或数据列关闭提示框，该函数里可以执行复杂的逻辑来返回需要的内容。      var content = '';      for (var i = 0; i < this.points.length; i++) {        if(i == this.points.length-1){          content += '<span style="font-size: 10px; color: ' + this.points[i].series.color + '">' + this.points[i].series.name + '</span>: ' + this.points[i].y +'℃'+'<br/>';        }else{          content += '<span style="font-size: 10px; color: ' + this.points[i].series.color + '">' + this.points[i].series.name + '</span>: ' + this.points[i].y +'%'+'<br/>';        }      };      var date = new Date();      var nowYear=date.getFullYear().toString();      var nowMonth=(date.getMonth() + 1).toString();      var nowDay=date.getDate().toString();       var nowHours=date.getHours().toString();       var nowMin=date.getMinutes().toString();       var nowSeconds=date.getSeconds().toString();       function timeAdd0(str) {         if(str.length<=1){           str='0'+str;         }         return str       }       nowYear=timeAdd0(nowYear) ;      nowMonth=timeAdd0(nowMonth) ;      nowDay=timeAdd0(nowDay) ;      nowHours=timeAdd0(nowHours) ;      nowMin=timeAdd0(nowMin);      nowSeconds=timeAdd0(nowSeconds)      content = '<span>' + nowYear + '/' + nowMonth + '/' + nowDay + ' ' + nowHours + ':' + nowMin + ':' + nowSeconds + ' year' + '</span><br/>' +content;      return content;    },