Like the data band, the Group Header band has three events.

 BeginRenderEvent

 EndRenderEvent 

 RenderingEvent

BeginRenderEvent

BeginRenderEvent is called before the group is rendered, that is, every time a new group is output. This event can be used to initialize data or variables, or to call a specific action.

EndRenderEvent

TEndRenderEvent is called after the group is output. Normally, the handler for this event does the data processing and total calculation.

RenderingEvent

RenderingEvent is called when the engine renders a row of data from a group.