Millisecond Forums

No, it's not possible. The textbox does not fire any accessible event upon each key press that occurs, i.e., you cannot count how often a given key was pressed when typing in a textbox.

Dave, thanks for your reply! I really appreciate it!
I did some research and found this FingerTapping task: http://www.millisecond.com/download/library/FingerTapping/.
It records the number of times participants press the space key.
I wonder if I could use its code and make some changes to it, so that I could record the number of times the backspace key being pressed when the participants type in the textbox? 

Unfortunately that isn't possible either.

Hi Dave, thanks for your reply. So is it possible to record how many times they've pressed the backspace key?

I'm afraid this is not possible, neither using <textbox> nor <openended>.