title: Do not select text input when ComboBox DropDown is opened
body: <p>I have a ComboBox in my WPF App, that I want to enter Text in, which is used to update the Content (Items) of the ComboBox.</p>
  
  <p>Whenever I enter a character, I want the updated Items to show. So I set <code>IsDropDownOpen = true;</code>, but this causes the Text which was entered to be selected.</p>
  
  <p>The result is: I type 1 char, the ComboBox DropDown is opened (and shows new Items), the char gets selected. I type a second char and it replaces the first one, because it was selected (duh)!</p>
  
  <p>How can I deselect all Text in the ComboBox? I obviously want to type more than 1 char whithout having to click on the ComboBox again to deselect all text...</p>
  
  <p>Code:</p>
  
  <pre><code>//MainWindow.xaml
  &lt;ComboBox x:Name="comboBoxItemID" HorizontalAlignment="Left" Height="38"
   VerticalAlignment="Top" Width="300" Canvas.Left="197" FontSize="21.333"
   IsEnabled="True" KeyUp="comboBoxItemID_KeyUp" IsEditable="True"/&gt;
  
  //comboBoxItemID_KeyUp()
  List&lt;InventorySearchResult&gt; Items = Invent.SearchArticle(this.comboBoxItemID.Text); //Get new Data
  comboBoxItemID.ItemsSource = Items;         //Update comboBox Data
  comboBoxItemID.DisplayMemberPath = "Name";
  comboBoxItemID.IsDropDownOpen = true;
  </code></pre>