Based on a previous subject :"How do I supress keystrokes in a month calendar cell" at your forum, I added some more code to implement some other keystroke for day ++, or day --. Please try the example code attached, and let me know why the second key "-" or "+" will get the error " object reference not set to an instance of an object" at DateTime dat = (DateTime)cc.Renderer.ControlValue;". Thanks.
Forum_407351.zip