expression.OnOpen
expression Required. An expression that returns one of the objects in the Applies To list.
Remarks
This property is helpful for programmatically changing the action Microsoft Access takes when an event is triggered. For example, between event calls you may want to change an expression's parameters, or switch from an event procedure to an expression or macro, depending on the circumstances under which the event was triggered.
The Open event occurs when a form is opened, but before the first record is displayed. For reports, the event occurs before a report is previewed or printed.
The OnOpen value will be one of the following, depending on the selection chosen in the Choose Builder window (accessed by clicking the Build button next to the On Open box in the form or report's Properties window):
- If Expression Builder is chosen, the value will be "=expression", where expression is the expression from the Expression Builder window.
- If Macro Builder is chosen, the value is the name of the macro.
- If Code Builder is chosen, the value will be "[Event Procedure]".
If the On Open box is blank, the property value is an empty string.
Example
The following example prints the value of the OnOpen property in the Immediate window for the "Purchase Order" report.
Debug.Print Reports("Purchase Order").OnOpen