查看Date.js

Date.today().previous().monday()

不知道它的性能如何，但这是可行的。

var today = new Date();
var day = today.getDay() || 7; // Get current day number, converting Sun. to 7
if( day !== 1 )                // Only manipulate the date if it isn't Mon.
    today.setHours(-24 * (day - 1));   // Set the hours to day number minus 1
                                         //   multiplied by negative 24
alert(today); // will be Monday

或作为一个函数:

# modifies _date_
function setToMonday( date ) {
    var day = date.getDay() || 7;  
    if( day !== 1 ) 
        date.setHours(-24 * (day - 1)); 
    return date;
}

setToMonday(new Date());

晚上好,

我更喜欢有一个简单的扩展方法:

Date.prototype.startOfWeek = function (pStartOfWeek) {
    var mDifference = this.getDay() - pStartOfWeek;

    if (mDifference < 0) {
        mDifference += 7;
    }

    return new Date(this.addDays(mDifference * -1));
}

你会注意到这实际上利用了我使用的另一个扩展方法:

Date.prototype.addDays = function (pDays) {
    var mDate = new Date(this.valueOf());
    mDate.setDate(mDate.getDate() + pDays);
    return mDate;
};

现在，如果你的周从周日开始，为pStartOfWeek参数传递一个“0”，如下所示:

var mThisSunday = new Date（）.startOfWeek（0）;

类似地，如果你的周从星期一开始，为pStartOfWeek参数传递一个“1”:

var mThisMonday = new Date（）.startOfWeek（1）;

问候,

区分本地时间和UTC时间是很重要的。我想用UTC找到一周的开始，所以我使用了下面的函数。

function start_of_week_utc(date, start_day = 1) {

// Returns the start of the week containing a 'date'. Monday 00:00 UTC is
// considered to be the boundary between adjacent weeks, unless 'start_day' is
// specified. A Date object is returned.

    date = new Date(date);
    const day_of_month = date.getUTCDate();
    const day_of_week = date.getUTCDay();
    const difference_in_days = (
        day_of_week >= start_day
        ? day_of_week - start_day
        : day_of_week - start_day + 7
    );
    date.setUTCDate(day_of_month - difference_in_days);
    date.setUTCHours(0);
    date.setUTCMinutes(0);
    date.setUTCSeconds(0);
    date.setUTCMilliseconds(0);
    return date;
}

要在给定时区中找到一周的开始，首先将时区偏移量添加到输入日期，然后从输出日期中减去时区偏移量。

const local_start_of_week = new Date(
    start_of_week_utc(
        date.getTime() + timezone_offset_ms
    ).getTime() - timezone_offset_ms
);

查看:moment.js

例子:

moment().day(-7); // last Sunday (0 - 7)
moment().day(7); // next Sunday (0 + 7)
moment().day(10); // next Wednesday (3 + 7)
moment().day(24); // 3 Wednesdays from now (3 + 7 + 7 + 7)

好处:也适用于node.js

周一上午00点到周一上午00点返回。

const now = new Date()
const startOfWeek = new Date(now.getFullYear(), now.getMonth(), now.getDate() - now.getDay() + 1)
const endOfWeek = new Date(now.getFullYear(), now.getMonth(), startOfWeek.getDate() + 7)