I know this has got to be easy! If one field is modified, I want to copy the before modified value into another field on the same form.
CurrentValueField = 2
PreviousValueField = 0
Now if CurrentValueField is modified to a 3, I want the 2 copied to the PreviousValueField.
CurrentValueField = 3
PreviousValueField = 2
CurrentValueField = 2
PreviousValueField = 0
Now if CurrentValueField is modified to a 3, I want the 2 copied to the PreviousValueField.
CurrentValueField = 3
PreviousValueField = 2