You can use the EventProcPrefix property to get the prefix portion of an event procedure name. For example, if you have a command button with an event procedure named Details_Click, the EventProcPrefix property returns the string "Details".
Setting
The EventProcPrefix property setting is a string expression.
This property is available only by using a macro or Visual Basic and is read-only in all views.
Remarks
Microsoft Access adds the prefix portion of an event procedure name to the event name with an underscore character (_).