form fields bootstrap 4 code example

Example 1: bootstrap select

<select class="custom-select">
  <option selected>Open this select menu</option>
  <option value="1">One</option>
  <option value="2">Two</option>
  <option value="3">Three</option>
</select>

Example 2: bootstrap form-control inline

<div class="form-group">
    <label for="birthday" class="col-xs-2 control-label">Birthday</label>
    <div class="col-xs-10">
        <div class="form-inline">
            <div class="form-group">
                <input type="text" class="form-control" placeholder="year"/>
            </div>
            <div class="form-group">
                <input type="text" class="form-control" placeholder="month"/>
            </div>
            <div class="form-group">
                <input type="text" class="form-control" placeholder="day"/>
            </div>
        </div>
    </div>
</div>