JSFiddle - React, Tailwind, and code Playground

by John Grivas

HTML

<select id="selected-attendees" class="form-control">
    <option value="volvo">Volvo</option>
    <option value="12345">Saab</option>
    <option value="mercedes">Mercedes</option>
    <option value="audi">Audi</option>
</select>
<input type="text" id="attendeeId" value="12345"/>

JavaScript

var exists = $("#selected-attendees").find('option[value=' + $('#attendeeId').val() + ']').length >0;

    if (exists) {
        //do if exists
        alert("yes");
    } else {
        //do because not exists
                alert("no");
    }