how can I compare dates in array to find the earliest one?

Question

I have a variable called dateArray with dates in it for example

[\"09/09/2009\", \"16/07/2010\", \"29/01/2001\"]

and I want to find the earlies

Answer 1

Sometimes the most basic approach is the best:

var dates = ["09/09/2009", "16/07/2010", "29/01/2001"];
var min = dates[0];
for(var i = 1; i < dates.length; i++) {
  if (fDate(dates[i]) < fDate(min))
    min = dates[i];
}

alert(min);

// create a proper Date object from the string
function fDate(s) {
  var d = new Date();
  s = s.split('/');
  d.setFullYear(s[2]);
  d.setMonth(s[1]);
  d.setDate(s[0]);
  return d;
}

The code I wrote for you above converts each string into a Date object, and then finds the minimum (the earliest date) from them. No string hacks, just straightforward date comparison. It returns the original string from the array.

Answer 2

   var dateArray = ["09/09/1980","09/09/2009", "16/07/2010", "29/01/1990"];
   var first = dateArray[0].split("/").reverse().join("-");
   var arrayLength = dateArray.length;
   for(var i=1; i< arrayLength; i++){
   second = dateArray[i].split("/").reverse().join("-");
     if (first > second){
        first = second;
     }
   }
alert(first);

Answer 3

You can get the earliest date by the below loop

var dateArray = ["09/09/2009", "16/07/2010", "29/01/2001"];
    alert(dateArray)//convert string to date object
var earliest = dateArray[0];
for(i=0; i<=dateArray.length; i++){
  var date1 = dateArray[i];
  if (date1 > earliest) {
     earliest = date1;

  }
}
alert(earliest)

Answer 4

The easiest way is to create dates object and the you can check grater/equal.. (date1 > date2)

Example to create date: Convert dd-mm-yyyy string to date

Answer 5

You can try with momentjs library:

var dateArray = ["09/09/2009", "16/07/2010", "29/01/2001"],
    format = 'DD/MM/YYYY',
    minDate = moment(dateArray[0], format),
    minDateKey = 0;

for (var i = 1; i < dateArray.length; i++) {
  var date = moment(dateArray[i], format);
  if (minDate > date) {
    minDate = date;
    minDateKey = i;
  }
}

alert(minDateKey);

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