Erhalten Woche des Jahres in JavaScript wie in PHP

Können Sie momentjs Bibliothek auch:

moment().format('W')

InformationsquelleAutor sixdays

Wie oben gesagt, aber ohne Klasse:

let now = new Date();
let onejan = new Date(now.getFullYear(), 0, 1);
week = Math.ceil( (((now - onejan) / 86400000) + onejan.getDay() + 1) / 7 );

InformationsquelleAutor nvd

getWeekOfYear: function(date) {
        var target = new Date(date.valueOf()),
            dayNumber = (date.getUTCDay() + 6) % 7,
            firstThursday;

        target.setUTCDate(target.getUTCDate() - dayNumber + 3);
        firstThursday = target.valueOf();
        target.setUTCMonth(0, 1);

        if (target.getUTCDay() !== 4) {
            target.setUTCMonth(0, 1 + ((4 - target.getUTCDay()) + 7) % 7);
        }

        return Math.ceil((firstThursday - target) /  (7 * 24 * 3600 * 1000)) + 1;
    }

Folgenden code timezone-unabhängig (UTC Datumsangaben verwendet) und arbeitet nach dem https://en.wikipedia.org/wiki/ISO_8601

InformationsquelleAutor Dmitry Volokh

Holen Sie sich die Wochennummer eines bestimmten Datum

function week(year,month,day) {
    function serial(days) { return 86400000*days; }
    function dateserial(year,month,day) { return (new Date(year,month-1,day).valueOf()); }
    function weekday(date) { return (new Date(date)).getDay()+1; }
    function yearserial(date) { return (new Date(date)).getFullYear(); }
    var date = year instanceof Date ? year.valueOf() : typeof year === "string" ? new Date(year).valueOf() : dateserial(year,month,day), 
        date2 = dateserial(yearserial(date - serial(weekday(date-serial(1))) + serial(4)),1,3);
    return ~~((date - date2 + serial(weekday(date2) + 5))/ serial(7));
}

Beispiel

console.log(
    week(2016, 06, 11),//23
    week(2015, 9, 26),//39
    week(2016, 1, 1),//53
    week(2016, 1, 4),//1
    week(new Date(2016, 0, 4)),//1
    week("11 january 2016")//2
);

InformationsquelleAutor Hans Petersen

Wenn Sie bereits in einer Eckigen Projekt, das Sie verwenden könnte,$filter('date').

Beispiel:

var myDate = new Date();
var myWeek = $filter('date')(myDate, 'ww');

InformationsquelleAutor Gabriel Furstenheim

Hier ist meine Umsetzung für die Berechnung der Wochennummer in JavaScript. korrigiert für Sommer-und winter-Zeit-offsets als gut.
Ich verwendet die definition in der Woche von diesem Artikel: ISO 8601

Wochen sind von Montag bis Sonntag, der 4. Januar immer in die erste Woche des Jahres.

//add get week prototype functions
//weeks always start from monday to sunday
//january 4th is always in the first week of the year
Date.prototype.getWeek = function () {
    year = this.getFullYear();
    var currentDotw = this.getWeekDay();
    if (this.getMonth() == 11 && this.getDate() - currentDotw > 28) {
        //if true, the week is part of next year 
        return this.getWeekForYear(year + 1);
    }
    if (this.getMonth() == 0 && this.getDate() + 6 - currentDotw < 4) {
        //if true, the week is part of previous year
        return this.getWeekForYear(year - 1);
    }
    return this.getWeekForYear(year);
}

//returns a zero based day, where monday = 0
//all weeks start with monday
Date.prototype.getWeekDay = function () {
    return  (this.getDay() + 6) % 7;
}

//corrected for summer/winter time
Date.prototype.getWeekForYear = function (year) {
    var currentDotw = this.getWeekDay();
    var fourjan = new Date(year, 0, 4);
    var firstDotw = fourjan.getWeekDay();
    var dayTotal = this.getDaysDifferenceCorrected(fourjan) //the difference in days between the two dates.
    //correct for the days of the week
    dayTotal += firstDotw; //the difference between the current date and the first monday of the first week, 
    dayTotal -= currentDotw; //the difference between the first monday and the current week's monday
    //day total should be a multiple of 7 now
    var weeknumber = dayTotal / 7 + 1; //add one since it gives a zero based week number.
    return weeknumber;
}

//corrected for timezones and offset
Date.prototype.getDaysDifferenceCorrected = function (other) {
    var millisecondsDifference = (this - other);
    //correct for offset difference. offsets are in minutes, the difference is in milliseconds
    millisecondsDifference += (other.getTimezoneOffset()- this.getTimezoneOffset()) * 60000;
    //return day total. 1 day is 86400000 milliseconds, floor the value to return only full days
    return Math.floor(millisecondsDifference / 86400000);
}

zum testen verwendete ich die folgende JavaScript-tests in Qunit

var runweekcompare = function(result, expected) {
    equal(result, expected,'Week nr expected value: ' + expected + ' Actual value: ' + result);
}

test('first week number test', function () {
    expect(5);
    var temp = new Date(2016, 0, 4); //is the monday of the first week of the year
    runweekcompare(temp.getWeek(), 1);
    var temp = new Date(2016, 0, 4, 23, 50); //is the monday of the first week of the year
    runweekcompare(temp.getWeek(), 1);
    var temp = new Date(2016, 0, 10, 23, 50); //is the sunday of the first week of the year
    runweekcompare(temp.getWeek(), 1);
    var temp = new Date(2016, 0, 11, 23, 50); //is the second week of the year
    runweekcompare(temp.getWeek(), 2);
    var temp = new Date(2016, 1, 29, 23, 50); //is the 9th week of the year
    runweekcompare(temp.getWeek(), 9);
});

test('first day is part of last years last week', function () {
    expect(2);
    var temp = new Date(2016, 0, 1, 23, 50); //is the first last week of the previous year
    runweekcompare(temp.getWeek(), 53);
    var temp = new Date(2011, 0, 2, 23, 50); //is the first last week of the previous year
    runweekcompare(temp.getWeek(), 52);
});

test('last  day is part of next years first week', function () {
    var temp = new Date(2013, 11, 30); //is part of the first week of 2014
    runweekcompare(temp.getWeek(), 1);
});

test('summer winter time change', function () {
    expect(2);
    var temp = new Date(2000, 2, 26); 
    runweekcompare(temp.getWeek(), 12);
    var temp = new Date(2000, 2, 27); 
    runweekcompare(temp.getWeek(), 13);
});

test('full 20 year test', function () {
    //expect(20 * 12 * 28 * 2);
    for (i = 2000; i < 2020; i++) {
        for (month = 0; month < 12; month++) {
            for (day = 1; day < 29 ; day++) {
                var temp = new Date(i, month, day);
                var expectedweek = temp.getWeek();
                var temp2 = new Date(i, month, day, 23, 50);
                var resultweek = temp.getWeek();
                equal(expectedweek, Math.round(expectedweek), 'week number whole number expected ' + Math.round(expectedweek) + ' resulted week nr ' + expectedweek);
                equal(resultweek, expectedweek, 'Week nr expected value: ' + expectedweek + ' Actual value: ' + resultweek + ' for year ' + i + ' month ' + month + ' day ' + day);
            }
        }
    }
});

InformationsquelleAutor martijn

Habe ich versucht, eine Menge zu bekommen, den kürzesten code, um die Wochennummer nach ISO-konform.

Date.prototype.getWeek=function(){
    var date=new Date(this);
    date.setHours(0,0,0,0);
    return Math.round(((date.setDate(this.getDate()+2-(this.getDay()||7))-date.setMonth(0,4))/8.64e7+3+(date.getDay()||7))/7)+"/"+date.getFullYear();}

Die variable date ist notwendig, um zu vermeiden, zu ändern, die original this. Ich verwendet die return-Werte der setDate() und setMonth() zu verzichten getTime() zu sparen code-Länge und ich habe eine expontial-Nummer für Millisekunden ein Tag anstelle von einer Multiplikation der einzelnen Elemente oder eine Zahl mit fünf Nullen. this ist das Datum, oder die Anzahl der Millisekunden, Rückgabewert ist String z.B. "49/2017".

InformationsquelleAutor Sven Huber

Den code-snippet, das funktioniert ziemlich gut für mich, ist dieses hier:

var yearStart = +new Date(d.getFullYear(), 0, 1);
var today = +new Date(d.getFullYear(),d.getMonth(),d.getDate());
var dayOfYear = ((today - yearStart + 1) / 86400000);
return Math.ceil(dayOfYear / 7).toString();

Beachten:

d ist meine Date, für die möchte ich die aktuelle Nummer der Woche.

Die + wandelt die Datumsangaben in zahlen (arbeiten mit Typoskript).

InformationsquelleAutor Vasco