根据年份获取当年所有周数，包含开始结束日期

返回结果：

.....
{
    year: 2023,
    week: '第48周',
    md: '11-27 - 12-03',
    s: '11-27',
    e: '12-03',
    text: '第48周(2023-11-27~2023-12-03)',
    value: 48
},
{
    year: 2023,
    week: '第49周',
    md: '12-04 - 12-10',
    s: '12-04',
    e: '12-10',
    text: '第49周(2023-12-04~2023-12-10)',
    value: 49
},
......

代码

const weekLostarr = [['01-01', '01-02', '01-03', '01-04', '01-05', '01-06'], ['01-01', '01-02', '01-03', '01-04', '01-05'], ['01-01', '01-02', '01-03', '01-04'], ['01-01', '01-02', '01-03'], ['01-01', '01-02'], ['01-01']]
//设置周下拉框
export function setweekOption(year) { //传入年份,字符串类型年份,'2020'
    year = new Date(year).getFullYear()
    let days = getDay(year || new Date().getFullYear())
    // console.log(days)
    let weeks = {};
    for (let i = 0; i < days.length; i++) {
        let weeksKeyLen = Object.keys(weeks).length;
        let daySplit = days[i].split('_');
        if (weeks[weeksKeyLen] === undefined) {
            weeks[weeksKeyLen + 1] = [daySplit[0]]
        } else {
            if (daySplit[1] == '1') {
                weeks[weeksKeyLen + 1] = [daySplit[0]]
            } else {
                weeks[weeksKeyLen].push(daySplit[0])
            }
        }
    }
    let option = []
    let weeksKeyLen = Object.keys(weeks).length;
    let isspan = false
    if (weeks[weeksKeyLen].length < 7) {
        isspan = true
        weeks[weeksKeyLen] = weeks[weeksKeyLen].concat(weekLostarr[weeks[weeksKeyLen].length-1])
    }
    for (let i = 1; i < weeksKeyLen + 1; i++) {
        let obj = {};
        obj.year = year
        obj.week = "第" + i + "周"
        obj.md = weeks[i][0] + ' - ' + weeks[i][weeks[i].length - 1]
        obj.s = weeks[i][0]
        obj.e = weeks[i][weeks[i].length - 1]

        obj.text = "第" + i + "周" + '(' + year + '-' + weeks[i][0] + '~' + (i == weeksKeyLen && isspan ? Number(year) + 1 : year) + '-' + weeks[i][weeks[i].length - 1] + ')';
        obj.value = i;
        option.push(obj)

    }
    return option;
}
function getDay(year) {
    let dates = [];
    for (let i = 1; i <= 12; i++) {
        for (let j = 1; j <= new Date(year, i, 0).getDate(); j++) {
            dates.push(formatNumber(i) + '-' + formatNumber(j) + '_' + new Date([year, formatNumber(i), formatNumber(j)].join('-')).getDay()) //返回当年所有日期（带星期数）
        }
    }
    let num = dates.findIndex(item => {
        return item.split('_')[1] == 1
    })
    dates = dates.slice(num)
    return dates;
}
function formatNumber(n) {
    return n.toString().length > 1 ? n : '0' + n
}