title: How can I find listbox item index with item value?
body: <p>my</p>
  
  <pre><code>MessageBox.Show(listbox.Items[0].ToString());
  </code></pre>
  
  <p>is </p>
  
  <pre><code>"abber"
  </code></pre>
  
  <p>how can I find listbox item index 0 with "abber"?</p>