The Style.Border property is used to set the border in GridGroupingControl cell. If you need the Border in every three columns, then please try using Style.Border.Right property with conditional statements in QueryCellStyleInfo event to achieve this behavior. The Right property is used to Draw the Border in Right side of the cell.
Refer the code below:
void gridGroupingControl1_QueryCellStyleInfo(object sender, GridTableCellStyleInfoEventArgs e)
{
if (((e.TableCellIdentity.ColIndex+2) % 3) == 0)
{
e.Style.Borders.Bottom = new GridBorder(GridBorderStyle.Solid, Color.Black);
}
}
Above code is user to draw the border in bottom in GGC. Please let me know if i misunderstood your query .
Let me know if you need more information.
Regards,
Vinish.