OK, here we go....
Tables have Fields. Fields store data. FIELDS do not have events!
Forms have controls. Controls can be unbound or bound to Fields in a table
(or a virtual table, known as a query). CONTROLS have events.
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How is the value for FieldA calculated? In VBA?
Let's say we have a form "MyForm" with a control (text box) named
"MyControl" that is bound to a field "FieldA" that is in "Table1". There is
code (or if you must, a macro) for the MyControl.AfterUpdate event.
So now something causes a calculation that causes a new value for FieldA.
If it is an update query, the new value is put into FieldA in Table1 .... no
event fires.
If the new value is assigned to the control "MyControl" (that is bound to
FieldA in Table1), no event fires because there wasn't user intervention.
From Help:
***Setting the value of a control by using a macro or Visual Basic doesn't
trigger these events.
***AfterUpdate macros and event procedures run only if you change the data
in a control.
***Changing data in a control by using Visual Basic or a macro containing
the SetValue action doesn't trigger these events for the control.
If you use code to store the complex calculated value in FieldA (of
Table1), you could call the after update event of the control "MyControl".
You could also use the same code to store the same calculated value in
"FieldB" of "Table2".
Just remember: updating values with code/macros doesn't cause an control
event to fire.
It took me a while to finally understand this. Hope I explained it well
enough.
