highcharts日期时间格式

如何为多曲线设置不同单位

subSeries[j].tooltip = { valueSuffix: ' ' + subSeries[j].unit }

如何格式化时间

this.chartOptions.tooltip.headerFormat = '<b>{point.x:%m-%d %H:%M:%S}</b><br>'

所有时间格式：

%a: weekday name (customizable)
%b: month name (customizable)
%d: day of month, zero-padded (01-31)
%e: day of month, space-padded ( 1-31)
%H: hours, 24-hour time, zero-padded (00-23)
%I: hours, 12-hour time, zero-padded (01-12)
%m: month, zero-padded (01-12)
%M: minutes, zero-padded (00-59)
%S: seconds, zero-padded (00-59)
%y: year (two digits)
%Y: year (four digits)
%p: am/pm
%P: AM/PM (uppercase version of %p)
%w: weekday as number (0-6, 0 being Sunday)