ComboBox.OnChange Property (Access)
Sets or returns the value of the On Change box in the Properties window of one of the objects in the Applies To list. Read/write String.
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 Change event occurs when the contents of a text box or the text portion of a combo box changes. It also occurs when you move from one page to another page in a tab control.
The OnChange 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 Change box in the object'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 Change box is blank, the property value is an empty string.