BCGControlBar Pro for MFC
void CBCGPChartAxis::ShowMajorGridLines ( BOOL  bShow = TRUE)

Shows or hides major grid lines.

Call this method to show or hide major grid lines.

You can also call CBCGPChartVisualObject::ShowAxisGridLines to show major and minor grid lines for an axis at once.

Parameters
bShowTRUE - show grid lines; FALSE - hide grid lines.