涨知识：如何根据确定时间段，获得当月第一天，最后一天，本周数组信息，范围内每天的信息。获得今天的日期

冷不防 2022-11-24 15:29 89阅读 0赞

<el-date-picker v-model="time" type="daterange" range-separator="至" start-placeholder="开始日期" end-placeholder="结束日期" @change="handleTime" />

// 月
    getMonth(MM) {  // MM的格式是YYYY-MM-DD
      let date = new Date(MM) 
      let month = (date.getMonth() + 1).toString().padStart(2, '0')
      let year = date.getFullYear()
      this.getParams.startDate = `${ year}-${ month}-01`
      let day = new Date(year, month, 0)
      this.getParams.endDate = `${ year}-${ month}-${ day.getDate()}`
    },
    // 周
    getWeek(dd) {  // dd的格式是Tue Aug 04 2020 00:00:00 GMT+0800 (中国标准时间)
       var timesStamp = dd.getTime(); 
       var currenDay = dd.getDay();
       var dates = [];
       for (var i = 0; i < 7; i++) { 
         dates.push(parseTime(new Date(timesStamp + 24 * 60 * 60 * 1000 * (i - (currenDay + 6) % 7)), '{y}-{m}-{d}'))
       }
       return dates
     },
     // 天
    getDay(stime, etime) {  // stime, etime的格式是YYYY-MM-DD
      //初始化日期列表，数组
      var diffdate = new Array();
      var i = 0;
      //开始日期小于等于结束日期,并循环
      while (stime <= etime) {  
        diffdate[i] = stime;
        var stime_ts = new Date(stime).getTime() //获取开始日期时间戳
        var next_date = stime_ts + (24 * 60 * 60 * 1000) //增加一天时间戳后的日期
        //拼接年月日，这里的月份会返回（0-11），所以要+1
        var next_dates_y = new Date(next_date).getFullYear() + '-';
        var next_dates_m = (new Date(next_date).getMonth() + 1 < 10) ? '0' + (new Date(next_date).getMonth() + 1) + '-' : (new Date(next_date).getMonth() + 1) + '-';
        var next_dates_d = (new Date(next_date).getDate() < 10) ? '0' + new Date(next_date).getDate() : new Date(next_date).getDate();
        stime = next_dates_y + next_dates_m + next_dates_d;
        i++; //增加数组key
      }
      return diffdate
    }
    // 当天日前
    var date = new Date();
    var dd = String(date.getDate()).padStart(2, '0');
    var mm = String(date.getMonth() + 1).padStart(2, '0');
    var yyyy = date.getFullYear();
    var currentDate = yyyy + '-' + mm + '-' + dd;

parseTime方法如下

export function parseTime(time, cFormat) { 
     if (arguments.length === 0) { 
       return null
     }
     const format = cFormat || '{y}-{m}-{d} {h}:{i}:{s}'
     let date
     if (typeof time === 'object') { 
       date = time
     } else { 
       if ((typeof time === 'string') && (/^[0-9]+$/.test(time))) { 
         time = parseInt(time)
       }
       if ((typeof time === 'number') && (time.toString().length === 10)) { 
         time = time * 1000
       }
       date = new Date(time)
     }
     const formatObj = { 
       y: date.getFullYear(),
       m: date.getMonth() + 1,
       d: date.getDate(),
       h: date.getHours(),
       i: date.getMinutes(),
       s: date.getSeconds(),
       a: date.getDay()
     }
     return format.replace(/{([ymdhisa])+}/g, (result, key) => { 
       const value = formatObj[key]
       // Note: getDay() returns 0 on Sunday
       if (key === 'a') { 
         return ['日', '一', '二', '三', '四', '五', '六'][value]
       }
       return value.toString().padStart(2, '0')
     })
    }

[某个日期所在的周一日期][Link 1]

[Link 1]: https://www.cnblogs.com/bookobe/p/8353549.html