title: How to wrap a div in jQuery?
body: <p>I have a <code>selectbox</code>:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
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  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;select&gt;
    &lt;option value="opt1"&gt;Optie nummer 1&lt;/option&gt;
    &lt;option value="opt2"&gt;Optie nummer 2&lt;/option&gt;
    &lt;option value="opt3"&gt;Optie nummer 3&lt;/option&gt;
  &lt;/select&gt;</code></pre>
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  <p>With a plugin I style the select boxes and then the HTML become:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
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  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div class="sb-custom"&gt;
    &lt;select tabindex="-1"&gt;
      &lt;option value="opt1"&gt;Optie nummer 1&lt;/option&gt;
      &lt;option value="opt2"&gt;Optie nummer 2&lt;/option&gt;
      &lt;option value="opt3"&gt;Optie nummer 3&lt;/option&gt;
    &lt;/select&gt;
  
    &lt;input type="text" class="sb-select" readonly="readonly"&gt;
  
    &lt;ul class="sb-dropdown"&gt;
      &lt;li class="selected"&gt;&lt;a href="."&gt;Optie nummer 1&lt;/a&gt;&lt;/li&gt;
      &lt;li&gt;&lt;a href="."&gt;Optie nummer 2&lt;/a&gt;&lt;/li&gt;
      &lt;li&gt;&lt;a href="."&gt;Optie nummer 3&lt;/a&gt;&lt;/li&gt;
    &lt;/ul&gt;
  &lt;/div&gt;</code></pre>
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  <p>Now I want when I add the class <code>small</code> add the <code>selectbox</code> that the <code>div "sb-costum"</code> get a the class small extra. So you get <code>&lt;div class="sb-custom small"&gt;</code></p>