By default, when an item is matched by the text entered in an editable RadComboBox, it will instantaneously be set as the SelectedItem of the control. The same result is observed when navigating through the items with the keyboard. Setting the UpdateSelectionOnLostFocus property to True overrides this behavior and the selection will only be updated when the focus is moved out of the control or the Enter key is pressed.
The property affects only an editable RadComboBox with single selection.
Example 1: Set the UpdateSelectionOnLostFocus property
<telerik:RadComboBox IsEditable="True" UpdateSelectionOnLostFocus="True"> <telerik:RadComboBoxItem Content="Item 1" /> <telerik:RadComboBoxItem Content="Item 2" /> <telerik:RadComboBoxItem Content="Item 3" /> </telerik:RadComboBox>
When the typed text does not match any of the items in the RadComboBox, the SelectedItem/SelectedValue property will be set to null, and the Text property of the control will hold the typed text. When the control loses focus, the typed text won't be cleared.
You can have a look at the Configurator demo from the WPF Controls Samples to get a better understanding of how the UpdateSelectionOnLostFocus property works.