title: Getting Which Radio Button is Checked in a Groupbox
body: <p>Found this in here. Could someone explain how this works? especially starting from the Function line.</p>
  
  <pre><code> Dim rButton As RadioButton = 
      GroupBox1.Controls
     .OfType(Of RadioButton)
     .Where(Function(r) r.Checked = True)
     .FirstOrDefault()
  </code></pre>
  
  <p>REFERENCE: <a href="https://stackoverflow.com/questions/6466952/how-to-get-a-checked-radio-button-in-a-groupbox">How to get a checked radio button in a groupbox?</a></p>