title: How to deleselect / blank a databound ComboBox? SelectedIndex = -1 does not work
body: <p>I am trying to deselect (blank out) a number of combo-boxes in my windows forms application. In my application I have a Reset method that sets the SelectedIndex for each combo to -1. All of my combo-boxes are databound, i.e. each combo-box is populated using a datasource.</p>
  
  <p>I have noticed that sometimes my Reset method works, i.e. it deselects the currently selected item and blanks the combo. However, other times it chooses the first item (SelectedIndex = 0) straight after I attempt to set it to -1. From a users point of view this looks like a bug as it doesn't always "clear" the form. </p>
  
  <p>According to MSDN:</p>
  
  <p>"To deselect the currently selected item, set the SelectedIndex to -1. You cannot set the SelectedIndex of a ComboBox item to -1 if the item is a data-bound item."</p>
  
  <p>Does anyone know of a work around?</p>
  
  <p>Many thanks</p>