Date string to Date using momentjs

You can parse string with multiple formats as described here.

If you need you can also pass locale parameter.

The following code shows a possible solution to your question:

var arr = ['31/10/93','10/31/93','93/10/31'];

for(var i=0; i< arr.length; i++){
  var m = moment.utc(arr[i], ['DD/MM/YY', 'MM/DD/YY', 'YY/MM/DD']);
  console.log(m.format('DD MMMM YYYY')); // 31 October 1993
}

<script src="//cdnjs.cloudflare.com/ajax/libs/moment.js/2.14.1/moment.min.js"></script>

This works fine for the input you gave as example, but may give you unexepcted results for inputs like 01/02/93. This string can represent both 1 February 1993 and 2 January 1993.

The suggested code will show 01 February 1993 because, as stated in the docs:

Moment uses some simple heuristics to determine which format to use. In order:

• Prefer formats resulting in valid dates over invalid ones.
• Prefer formats that parse more of the string than less and use more of the format than less, i.e. prefer stricter parsing.
• Prefer formats earlier in the array than later

If you need a JavaScript Date from moment object you can use toDate() method, while if you need Unix timestamp you can use valueOf() or unix().

After your comment, I can suggest to get "localized" format using moment.localeData(). Using longDateFormat('L') you can get localized format string and then use it in the parsing function. For example, longDateFormat('L') will return MM/DD/YYYY for us locale and DD/MM/YYYY for it. Code sample:

var s = '01/02/93';

function formatSample(s){
  var ldf = moment.localeData().longDateFormat('L');
  return moment.utc(s, [ldf, 'YY/MM/DD']).format('DD MMMM YYYY');
}

moment.locale('us');
formatSample(s); // 02 January 1993
moment.locale('it');
formatSample(s); // 01 febbraio 1993

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.14.1/moment-with-locales.min.js"></script>