Don't select item on key down/up

[bugproof]

Would be nice to have a setting to only select on pressing Enter, currently, when you press up/down arrows it changes the selection.

[vain0x]

Thanks. It would be nice.

Modifying the behavior of SelectedItem seems difficult.

Instead, it may be easy to make a property to hold the committed item, and update the property by watching Enter/Click events.

This mechanism can be implemented outside the library by using attached dependency property. I will try when I feel like doing.

[bugproof]

Yes, I was trying to modify this behaviour but it's all internal. If you have any idea how to do this with the original combo box that would be great. Currently, all I can think of is implementing your own Combobox using listbox and textbox.

dotnet/wpf#1044