title: C# Windows Forms app - Clear ComboBox selected text from another ComboBox
body: <p>Windows Forms application (c#).
  I have two ComboBoxes. 
  If I select an item in one, I want the text in the other one to be blank.</p>
  
  <p>This is what I have:</p>
  
  <pre><code>private void ComboBox1_SelectedIndexChanged(object sender, EventArgs e)
  {
  ComboBox2.Text = "";
  }
  
  private void ComboBox2_SelectedIndexChanged(object sender, EventArgs e)
  {
  ComboBox1.Text = "";
  }
  </code></pre>
  
  <p>... but as you can see, when I make a selection in one, the text in both ComboBoxes get cleared.</p>
  
  <p>How to accomplish this?</p>
  
  <p>Thank you.</p>