title: mimic the auto height increase in textbox in messaging WP7
body: <p>I want to make my textbox height increases as the user inputs more text or presses Enter</p>
  
  <p>The problem is you cannot find out when the user has reached the end of the textbox to increase it's height, you cannot count characters because each character has it's own with</p>
  
  <p>also the Enter key to make a new line has it's own problems, it only goes to the beginning of the current line if you used </p>
  
  <pre><code>    private void textBox1_KeyDown(object sender, KeyEventArgs e)
      {
  
          if (e.Key.Equals(Key.Enter))
              textBox1.Text += System.Environment.NewLine;            
  
      }
  </code></pre>
  
  <p>any idea how to do this ?</p>