JSFiddle - React, Tailwind, and code Playground
HTML
<select id="selecty" multiple size=6 width=150 style="width:150px" name="ToLB" >
<option value="monkey">Monkey</option>
</select>
JavaScript
var listarray = new Array();
var select = document.getElementById('selecty');
for(var i = 0; i < select.options.length; i++){
listarray.push(select.options[i].value);
}
console.log(listarray);