如何从 javascript 中输入的日期获取周数？

Question

我正在尝试获取当前日期/特定日期所在的周数。任何有关逻辑构建的建议都会有所帮助。

Answer 1

function getWeekNumber(thisDate) {
var dt = new Date(thisDate);
var thisDay = dt.getDate();

var newDate = dt;
newDate.setDate(1); // first day of month
var digit = newDate.getDay();

var Q = (thisDay + digit) / 7;

var R = (thisDay + digit) % 7;

if (R !== 0) return Math.ceil(Q);
else return Q;}

getWeekNumber("07/31/2016");

Answer 2

let _ = new Date,
    __ = ~~((new Date(_.getFullYear(), 0, 0) - _) / 36e5 * 24),
    ___ = (__ - __ % 7) / 7;