Question

I have a form in MS Access which has 3 input fields ([Day1], [Day2], and [Day3]), and one field ([Total]) which shows the total of these three fields, by using ControlSource=[Day1]+[Day2]+[Day3].

Now, I want to update another field based on changes in [Total].
In other words, ‘on change’ of the [Total] field.

I tried to use the Change event and the AfterUpdate event, but neither of them trigger when the change is coming through the ControlSource.

Of course, I could update the field by executing the AfterUpdate code of each of the separate fields, but this feels less elegant.

Is there any event which triggers ‘on change through control source’ which I could use for this purpose?

Answer 1

As far as I know, there is no way to have an event fire when a calculated control (like your Total control) changes its calculated value. I’ve found that there are two approaches that have worked in the past for me:

#1: Do as you said and tie the update of the “other” field to the AfterUpdate events of Day1, Day2, and Day3 controls.

#2: Tie the update of the “other” field to the AfterUpdate method of the form itself. After the record changes are committed (e.g., after a requery or changing records), you have persistent data from which to make your update.