Hi Helmy,
Thank you for writing.
For our small editors we use the standard TextBox control for the textbox part. In order to use the KeyDown event of RadSpinEditor, please subscribe to the KeyDown event of its TextBoxItem:
We will consider improving the API of RadSpinEditor allowing you to directly work with the KeyDown event of the control.
I hope this helps.
Best wishes,
Nikolay
the Telerik team
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