JSFiddle - React, Tailwind, and code Playground

by Omar X

HTML

<script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.11.1/jquery.validate.js"></script>
<script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.11.1/additional-methods.js"></script>
<form id="form1" mrthod="get" action="#">
    <div date-role="fieldcontain" class="ui-hide-label">
        <label for="best_contact_method">Best Contact Method</label>
        <select data-theme="a" id="best_contact_method" name="best_contact_method" class="required" data-native-menu="false">
            <option>Best Contact Method</option>
            <option value="email">Email</option>
            <option value="daytime_phone">Daytime Phone</option>
            <option value="evening_phone">Evening Phone</option>
        </select>
    </div>
    <div data-role="fieldcontain" class="ui-hide-label">
        <label for="daytime_phone" id="daytime_phone_label">Daytime Phone</label>
        <input type="text" id="daytime_phone" name="daytime_phone" placeholder="Daytime Phone" />
    </div>
    <div data-role="fieldcontain" class="ui-hide-label">
        <label for="evening_phone" id="evening_phone_label">Evening Phone</label>
        <input type="text" id="evening_phone" name="evening_phone" placeholder="Evening Phone" />
    </div>
    <div data-role="fieldcontain" class="ui-hide-label">
        <label for="email" id="email_label">Email</label>
        <input type="text" id="email" name="email" placeholder="Email" />
    </div>
    <button type="submit" data-theme="a" name="submit" id="submit" value="validate">Validate</button>
</form>

JavaScript

$("#best_contact_method").on('change', function () {
    var item = $("select option:selected").val();
    switch (item) {
        case "email":
            $("#email").addClass("required email");
            $("#daytime_phone, #evening_phone").removeClass("required phoneUS");
            break;
        case "daytime_phone":
            $("#daytime_phone").addClass("required phoneUS");
            $("#email, #evening_phone").removeClass("required phoneUS email");
            break;
        case "evening_phone":
            $("#evening_phone").addClass("required phoneUS");
            $("#email, #daytime_phone").removeClass("required phoneUS email");
            break;
    }
    $("#form1").validate();
});