JSFiddle - React, Tailwind, and code Playground

HTML

From :<input type='text' id='txtDate1' /> <br/>
To :<input type='text' id='txtDate2' />
   <br><button>number of days</button>

JavaScript

$(document).ready(function(){
    var arrayable = ['2015/07/22', '2015/07/23'];

$('#txtDate1, #txtDate2').datepicker({
    minDate: 1,
    dateFormat: 'yy/mm/dd',
    beforeShowDay: function (date) {

    var datestring = jQuery.datepicker.formatDate('yy/mm/dd', date);
        if ($.inArray(datestring, arrayable) != -1 ) {
             return [false];
         } 
    var weekenddate = $.datepicker.noWeekends(date);
     return weekenddate; 
    }
});



   
        var start   = $('#txtDate1').datepicker('getDate');
        var end = $('#txtDate2').datepicker('getDate');
        var days   = (end - start)/1000/60/60/24;
        
   
});