Hello Dan Parker,
Unfortunately, you cannot convert the text to upper case while the typing occurs. The solution would have been to handle the PreviewKeyDown event and check if Shift is pressed and CapsLock is on. You can find out about the Shift, but the CapsLock's state is out of reach.
The other approach - handling the DocumentContentChanged event will not work, as it is fired with some delay.
All the best,
the Telerik team
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