时间戳转化为时间

在项目中，我们经常会遇到需要对时间戳进行处理，下面分为几种情况进行说明：

(1)获取系统当前时间，并将其格式化 （eg. 2018-01-08）

  var formatDate = function () {
                var date = new Date();
                var y = date.getFullYear();
                var m = date.getMonth() + 1;
                var d = date.getDate();
                m = m < 10 ? ("0" + m) : m;
                d = d < 10 ? ("0" + d) : d;
                return y + "-" + m + "-" + d + " ";
  }

formatDate();

　

（2）获取时间是周几（eg.周四）

    let time=new Date(2018-01-02)
    let weekDay="星期" + "日一二三四五六".charAt(time.getDay());
    console.log(weekDay)      //星期四

　　

（3）将两个时间戳的差值转化为具体的用时(eg.历时2.1周)

                let seconds = 1000;
                let minute = seconds * 60;
                let hour = minute * 60;
                let day = hour * 24;
                let month = day * 30;

               let diffValue = 1245653280;
                let monthC = diffValue / month;
                let weekC = diffValue / (7 * day);
               let dayC = diffValue / day;
                let hourC = diffValue / hour;
                let minC = diffValue / minute;
                let secC = diffValue / seconds;
                if (monthC >= 1) {
                    this.uTime = parseFloat(monthC.toFixed(1)) + "个月";
                }
                else if (weekC >= 1) {
                    this.uTime = parseFloat(weekC.toFixed(1)) + "周";
                }
                else if (dayC >= 1) {
                    this.uTime = parseFloat(dayC.toFixed(1)) + "天";
                }
                else if (hourC >= 1) {
                    this.uTime = parseFloat(hourC.toFixed(1)) + "小时";
                }
                else if (minC >= 1) {
                    this.uTime = parseFloat(minC.toFixed(1)) + "分钟";
                } else {
                    this.uTime = parseFloat(secC.toFixed(1)) + "秒";
                }