XPTable.Models.Table.PaintGridRowsColumnsOnlyParent C# (CSharp) Method

        void PaintGridRowsColumnsOnlyParent(PaintEventArgs e, Pen gridPen)
        {
            if (this.TopIndex <= -1)
            {
                return;
            }

            int yline = this.CellDataRect.Y - 1;
            int rowright = this.GetGridlineYMax(e);

            int displayRectangleX = this.DisplayRectangleLeft;
            ColumnCollection columns = this.ColumnModel.Columns;
            RowCollection rows = this.TableModel.Rows;

            // Need to draw each row grid at its correct height
            for (int irow = this.TopIndex; irow < this.TableModel.Rows.Count; irow++)
            {
                if (yline > e.ClipRectangle.Bottom)
                {
                    break;
                }

                if (yline >= this.CellDataRect.Top)
                {
                    e.Graphics.DrawLine(gridPen, e.ClipRectangle.Left, yline, rowright, yline);
                }

                Row row = rows[irow];

                yline += row.Height;

                // Only draw columns on parent.
                if (row.Parent != null)
                {
                    continue;
                }

                int right = displayRectangleX;

                // Draw columns
                int columnCount = columns.Count;
                for (int i = 0; i < columnCount; i++)
                {
                    if (!columns[i].Visible)
                    {
                        continue;
                    }

                    right += columns[i].Width;

                    var flags = row.InternalGridLineFlags;
                    if (i != columnCount - 1 && !flags[i])
                    {
                        continue;
                    }

                    if (right >= e.ClipRectangle.Left && right <= e.ClipRectangle.Right)
                    {
                        e.Graphics.DrawLine(gridPen, right - 1, yline, right - 1, yline + row.Height);
                    }
                }
            }

            // Now draw the final gridline under the last row (if visible)
            // TODO Make this option selectable via a parameter?
            if (yline < e.ClipRectangle.Bottom)
            {
                e.Graphics.DrawLine(gridPen, e.ClipRectangle.Left, yline, rowright, yline);
            }
        }