JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/overcast/jquery-ui.css">
<input type="text" class="datepicker" id="dp1">

<a href="javascript:;" class="tab" name="1,3">test button</a>

JavaScript

$(document).ready(function(){
    
    var pickable = ["2","3","4","5"];
    
    function closedDays(date){
        var sDate = date.getDay().toString();
        if ($.inArray(sDate, pickable) == -1) return [false,"",""];
        else return [true, ""];
    }

    $(".tab").click(function () { 
       pickable =  $(this).attr("name").split(",");
         closedDays;
    });
    
    $(".datepicker").each(function() {
        $(this).datepicker({
            beforeShowDay:  closedDays
        });
    });
    
   
    
});