title: Add string with List to a multiline textbox
body: <p>I'm trying to add a <code>list</code> and a <code>string</code> in a <code>textbox</code> with this code</p>
  
  <pre><code>ilaninfotextbox.Text = string.Join(Environment.NewLine, ilantextinner, combinelist);
  </code></pre>
  
  <p><code>ilantextinner</code> is a <code>string</code> and shows correctly on the textbox</p>
  
  <p><code>ilantextinner</code> is a <code>List&lt;string&gt;</code> with 20 lines in it</p>
  
  <p>But <code>ilantextinner</code> list is showing like this in the textbox:</p>
  
  <pre><code>System.Collections.Generic.List`1[System.String]
  </code></pre>
  
  <p>How can I show the contents of <code>ilantextinner</code> in the textbox?</p>
  
  <p>Note: If I use only <code>ilantextinner</code> contents are shown correctly.</p>