Jquery-Selektor, um alle Eingaben mit einem Wert abzurufen

let $inputs = $('.some-input-class').filter((i, el) => !!el.value.trim())
$inputs.addClass('valid');

.some-input-class {
  display: block;
  margin: 0 0 10px;
}
.valid {
   border: 2px solid #0C0;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="text" value="foo" class="some-input-class" />
<input type="text" value="bar" class="some-input-class" />
<input type="text" value="" class="some-input-class" />
<input type="text" class="some-input-class" />

<select class="some-input-class">
  <option value="">Please select...</option>
  <option value="lorem">Lorem ipsum</option>
</select>

<select class="some-input-class">
  <option value="">Please select...</option>
  <option value="lorem" selected>Lorem ipsum</option>
</select>