To create an event procedure that is executed when the Change event occurs, set the OnChange property to [Event Procedure], and click the Build button.
Private Sub controlname_Change( )
The Change event procedure uses the following argument.
| Argument | Description |
| controlname | A string that is the name of the control affected by the Change event procedure. |
You can’t cancel the Change event.
To prevent a cascading event, avoid creating a Change event procedure for a control that alters the control’s contents. If you do create such an event procedure, be sure to set a variable that prevents further changes while the current change is in progress.
Change Event — Macros.
The following example counts the number of characters entered in a text box. If more than three characters are entered, a message is displayed and the count is reset to 0.
To try this example, add the following code to the Declarations section of a module for a form named Orders that contains a text box called ShipRegion.
Private Sub ShipRegion_Change()
' Declare variable as static to preserve value between calls.
Static intLetter As Integer
' Check to see how many letters have been entered.
If intLetter < 3 Then
intLetter = intLetter + 1
' If more than three, reset value of text box.
Else
MsgBox "Only three characters are allowed."
intLetter = 0
Forms!Orders!ShipRegion.Undo
End IfSub