JSFiddle - React, Tailwind, and code Playground

HTML

<label for="autocomplete">Select a programming language: </label>
<input id="autocomplete" data-value>
<button id="getValue">Value</button>

JavaScript

$( "#autocomplete" ).autocomplete({
      source: [ { label:"c++", value:1 }, { label: "java", value:2 }, { label: "javascript", value:3 } ],
    focus: function( event, ui ) {
        $( "#autocomplete" ).val( ui.item.label );
        return false;
      },
      select: function( event, ui ) {
        $( "#autocomplete" ).val( ui.item.label );
        $( "#autocomplete" ).attr("data-value",ui.item.value);
        return false;
      }
    });

$("#getValue").click(function(){
    alert($( "#autocomplete" ).attr("data-value"));
});