js 中国标准时间转时分秒

function dateFormat(date) {
        //日期格式化
        var d = new Date(date)
        let year = d.getFullYear()
        let month = d.getMonth() + 1
        month = '0' + month
        month = month.substring(month.length - 2)
        let day = '0' + d.getDate()
        day = day.substring(day.length - 2)
        let hour = '0' + d.getHours()
        hour = hour.substring(hour.length - 2)
        let m = '0' + d.getMinutes()
        m = m.substring(m.length - 2)
        let s = '0' + d.getSeconds()
        s = s.substring(s.length - 2)
        let format = year + '-' + month + '-' + day + ' ' + hour + ':' + m + ':' + s
        return format
      }