title: How to check if an <li> element has a specific value
body: <p>can i Check with JS or JQuery whether an list contains a specific Value or not?</p>
  
  <p>My Code:</p>
  
  <p>HTML:</p>
  
  <pre><code>  &lt;ul class="list-group list-group-flush" id="liste"&gt;
    &lt;/ul&gt;
  </code></pre>
  
  <p>JavaScript:</p>
  
  <pre><code>&lt;script type="text/javascript"&gt;
    document.getElementById('Add').onclick = function() {
      var Nutzer = document.getElementById('Suche').value;
      var Liste = document.getElementById('liste');
      if (! $("li:has(Test)")) {
        var entry = document.createElement('li');
        entry.setAttribute( 'class', 'list-group-item' );
        entry.appendChild(document.createTextNode(Nutzer));
        Liste.appendChild(entry);
      }
  }
  &lt;/script&gt;
  </code></pre>
  
  <p>I only found Solutions with li:contains but that is not what I want.</p>