title: Convert GridLength to Double
body: <p>I have  a TextBox called <code>addTextBox</code> which is inside a row called <code>addTextBoxRow</code> whose height is <code>500*</code></p>
  
  <p>I want to assign the height of the <code>addTextBoxRow</code> to <code>addTextBox</code> whenever the layout changes.</p>
  
  <p>But when I tried with <code>addTextBox.Height = addTextBoxRow.Height</code>, it gives me an error that it cannot implicitly convert type 'Windows.UI.Xaml.GridLength' to 'double'.</p>