배열의 최소 / 최대 날짜?

배열의 최소 / 최대 날짜?

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날짜 배열에서 최소 및 최대 날짜를 어떻게 찾을 수 있습니까? 현재 다음과 같은 배열을 만들고 있습니다.

var dates = [];
dates.push(new Date("2011/06/25"))
dates.push(new Date("2011/06/26"))
dates.push(new Date("2011/06/27"))
dates.push(new Date("2011/06/28"))

이 작업을 수행하는 내장 함수가 있습니까? 아니면 직접 작성해야합니까?

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코드는 IE, FF, Chrome으로 테스트되었으며 제대로 작동합니다.

var dates=[];
dates.push(new Date("2011/06/25"))
dates.push(new Date("2011/06/26"))
dates.push(new Date("2011/06/27"))
dates.push(new Date("2011/06/28"))
var maxDate=new Date(Math.max.apply(null,dates));
var minDate=new Date(Math.min.apply(null,dates));

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다음과 같은 것 :

var min = dates.reduce(function (a, b) { return a < b ? a : b; }); 
var max = dates.reduce(function (a, b) { return a > b ? a : b; });

Chrome 15.0.854.0 dev에서 테스트 됨

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_.min및 _.max날짜의 배열에서 작동; Lodash 또는 Underscore를 사용하는 경우이를 사용하고 아직 사용하지 않은 경우 Lodash (이러한 많은 유틸리티 기능을 제공하는) 사용을 고려하십시오.

예를 들면

_.min([
    new Date('2015-05-08T00:07:19Z'),
    new Date('2015-04-08T00:07:19Z'),
    new Date('2015-06-08T00:07:19Z')
])

배열의 두 번째 날짜를 반환합니다 (가장 빠른 날짜이기 때문).

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날짜는 UNIX epoch (숫자)로 변환되므로 Math.max / min을 사용하여 찾을 수 있습니다.

var maxDate = Math.max.apply(null, dates)
// convert back to date object
maxDate = new Date(maxDate)

(Chrome에서만 테스트되었지만 대부분의 브라우저에서 작동합니다)

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function sortDates(a, b)
{
    return a.getTime() - b.getTime();
}

var dates = [];

dates.push(new Date("2011/06/26"))
dates.push(new Date("2011/06/28"))
dates.push(new Date("2011/06/25"))
dates.push(new Date("2011/06/27"))

var sorted = dates.sort(sortDates);
var minDate = sorted[0];
var maxDate = sorted[sorted.length-1];

데모 : http://jsfiddle.net/AlienWebguy/CdXTB/

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** 분산 연산자 사용 | ES6 **

let datesVar = [ 2017-10-26T03:37:10.876Z,
  2017-10-27T03:37:10.876Z,
  2017-10-23T03:37:10.876Z,
  2015-10-23T03:37:10.876Z ]

Math.min(...datesVar);

That will give the minimum date from the array.

Its shorthand Math.min.apply(null, ArrayOfdates);

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ONELINER:

var min=dates.sort((a,b)=>a-b)[0], max=dates.slice(-1)[0];

result in variables min and max, complexity O(nlogn), editable example here. If your array has no-date values (like null) first clean it by dates=dates.filter(d=> d instanceof Date);.

var dates = [];
dates.push(new Date("2011-06-25")); // I change "/" to "-" in "2011/06/25"
dates.push(new Date("2011-06-26")); // because conosle log write dates 
dates.push(new Date("2011-06-27")); // using "-".
dates.push(new Date("2011-06-28"));

var min=dates.sort((a,b)=>a-b)[0], max=dates.slice(-1)[0];

console.log({min,max});

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var max_date = dates.sort(function(d1, d2){
    return d2-d1;
})[0];

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Same as apply, now with spread :

const maxDate = new Date(Math.max(...dates));

(could be a comment on best answer)

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The above answers do not handle blank/undefined values to fix this I used the below code and replaced blanks with NA :

function getMax(dateArray, filler) {
      filler= filler?filler:"";
      if (!dateArray.length) {
        return filler;
      }
      var max = "";
      dateArray.forEach(function(date) {
        if (date) {
          var d = new Date(date);
          if (max && d.valueOf()>max.valueOf()) {
            max = d;
          } else if (!max) {
            max = d;
          }
        }
      });
      return max;
    };
console.log(getMax([],"NA"));
console.log(getMax(datesArray,"NA"));
console.log(getMax(datesArray));

function getMin(dateArray, filler) {
 filler = filler ? filler : "";
  if (!dateArray.length) {
    return filler;
  }
  var min = "";
  dateArray.forEach(function(date) {
    if (date) {
      var d = new Date(date);
      if (min && d.valueOf() < min.valueOf()) {
        min = d;
      } else if (!min) {
        min = d;
      }
    }
  });
  return min;
}

console.log(getMin([], "NA"));
console.log(getMin(datesArray, "NA"));
console.log(getMin(datesArray));

I have added a plain javascript demo here and used it as a filter with AngularJS in this codepen

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This is a particularly great way to do this (you can get max of an array of objects using one of the object properties): Math.max.apply(Math,array.map(function(o){return o.y;}))

This is the accepted answer for this page: Finding the max value of an attribute in an array of objects

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Using Moment, Underscore and jQuery, to iterate an array of dates.

Sample JSON:

"workerList": [{        
        "shift_start_dttm": "13/06/2017 20:21",
        "shift_end_dttm": "13/06/2017 23:59"
    }, {
        "shift_start_dttm": "03/04/2018 00:00",
        "shift_end_dttm": "03/05/2018 00:00"        
    }]

Javascript:

function getMinStartDttm(workerList) {  
    if(!_.isEmpty(workerList)) {
        var startDtArr = [];
        $.each(d.workerList, function(index,value) {                
            startDtArr.push(moment(value.shift_start_dttm.trim(), 'DD/MM/YYYY HH:mm')); 
         });            
         var startDt = _.min(startDtArr);           
         return start.format('DD/MM/YYYY HH:mm');
    } else {
        return '';
    }   
}

Hope it helps.

참고URL : https://stackoverflow.com/questions/7143399/min-max-of-dates-in-an-array