The control also fires the StartReport event at this time.

The difference between the regular event and the VBScript property is that the handler for the regular event belongs to the application, and should thus be used to support tasks that are independent of the report. For example, to display a message on the main window when rendering starts.

The VBScript handler in the property belongs to the report, and will be executed regardless of the application. For example, a report might contain a VBScript handler that resets global variables in the VBScript context when a report starts rendering.

Reference

C1Report Class
C1Report Members