How to create datepicker using JavaScript in Acrobat DC Pro?

The new Date Picker is not Acrobat Pro dependant, it is Acrobat Reader dependant.

I mean that only the latest Acrobat (Reader, Pro and Standard) will display the Date Picker in Date fields, older versions will never display the Date Picker, even if the form was made with the latest DC release.

How to create date-picker using JavaScript in Acrobat DC Pro?

Hi.

You don't need to re-invent the wheel, this one is already made: http://abracadabrapdf.net/utilities-in-english/acrobat-utilities/magicdate-picker/

The latest release of Adobe Acrobat DC and the free Adobe Reader DC will automatically display a date picker when you have  text field that uses a date format. All you need to do is create a date field, and set the correct format options:

The date field then shows a little triangle on the right. When you click on that, you get the date picker:

Keep in mind that when you open the file in an older version of Reader or Acrobat, the date picker will not show up - you can still enter the date manually.