Question

I have an editable WPF ComboBox with TextSearchEnabled. I need to force the user’s text input to uppercase when they type to filter the ComboBox.

I was thinking of modifying the textbox that is part of the control (named ‘PART_EditableTextBox’) to set CharacterCasing=”Upper”, however I can’t quite figure out how to do this.

Do I need to use a trigger, or modify the template in some way?

Answer 1

This works and seems like a reasonable solution:

protected void winSurveyScreen_Loaded(object sender, RoutedEventArgs e)
{
    (comboBox.Template.FindName("PART_EditableTextBox", cbObservation) as TextBox).CharacterCasing = CharacterCasing.Upper;
}

Ensure that the combobox is not collapsed on loaded otherwise the template will not be found.