#region"合并单元格的测试"

        private int? nextrow = null;

        private int? nextcol = null;

        private void dataGridView1_CellFormatting(object sender, System.Windows.Forms.DataGridViewCellFormattingEventArgs e)

        ...{

            if (this.dataGridView1.Columns["description"].Index == e.ColumnIndex && e.RowIndex >= 0)

            ...{

                if (this.nextcol != null & e.ColumnIndex == this.nextcol)

                ...{

                    e.CellStyle.BackColor = Color.LightBlue;

                    this.nextcol = null;

                }

                if (this.nextrow != null & e.RowIndex == nextrow)

                ...{

                    e.CellStyle.BackColor = Color.LightPink;

                    this.nextrow = null;

                }

                if (e.RowIndex != this.dataGridView1.RowCount - 1)

                ...{

                    if (e.Value.ToString() == this.dataGridView1.Rows[e.RowIndex + 1].Cells[e.ColumnIndex].Value.ToString())

                    ...{

                        e.CellStyle.BackColor = Color.LightPink;

                        nextrow = e.RowIndex + 1;

                    }

                }



            }

            if (this.dataGridView1.Columns["name"].Index == e.ColumnIndex && e.RowIndex >= 0)

            ...{

                if (e.Value.ToString() == this.dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex + 1].Value.ToString())

                ...{

                    e.CellStyle.BackColor = Color.LightBlue;

                    nextcol = e.ColumnIndex + 1;

                }

            }

        }

        //==========================

       

        //绘制单元格

        private void dataGridView1_CellPainting(object sender, System.Windows.Forms.DataGridViewCellPaintingEventArgs e)

        ...{



 



            //纵向合并

            if (this.dataGridView1.Columns["description"].Index == e.ColumnIndex && e.RowIndex >= 0)

            ...{



                using (

                    Brush gridBrush = new SolidBrush(this.dataGridView1.GridColor),

                    backColorBrush = new SolidBrush(e.CellStyle.BackColor))

                ...{

                    using (Pen gridLinePen = new Pen(gridBrush))

                    ...{

                        // 擦除原单元格背景

                        e.Graphics.FillRectangle(backColorBrush, e.CellBounds);

                        /**/////绘制线条,这些线条是单元格相互间隔的区分线条,

                        ////因为我们只对列name做处理,所以datagridview自己会处理左侧和上边缘的线条

                        if (e.RowIndex != this.dataGridView1.RowCount - 1)

                        ...{

                            if (e.Value.ToString() != this.dataGridView1.Rows[e.RowIndex + 1].Cells[e.ColumnIndex].Value.ToString())

                            ...{



                                e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1,

                                e.CellBounds.Right - 1, e.CellBounds.Bottom - 1);//下边缘的线

                                //绘制值

                                if (e.Value != null)

                                ...{

                                    e.Graphics.DrawString((String)e.Value, e.CellStyle.Font,

                                        Brushes.Crimson, e.CellBounds.X + 2,

                                        e.CellBounds.Y + 2, StringFormat.GenericDefault);

                                }

                            }

                        }

                        else

                        ...{

                            e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1,

                                e.CellBounds.Right - 1, e.CellBounds.Bottom - 1);//下边缘的线

                            //绘制值

                            if (e.Value != null)

                            ...{

                                e.Graphics.DrawString((String)e.Value, e.CellStyle.Font,

                                    Brushes.Crimson, e.CellBounds.X + 2,

                                    e.CellBounds.Y + 2, StringFormat.GenericDefault);

                            }

                        }

                        //右侧的线

                        e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1,

                            e.CellBounds.Top, e.CellBounds.Right - 1,

                            e.CellBounds.Bottom - 1);



                        e.Handled = true;

                    }

                }

            }



            //横向合并

            if (this.dataGridView1.Columns["name"].Index == e.ColumnIndex && e.RowIndex >= 0)

            ...{



                using (

                    Brush gridBrush = new SolidBrush(this.dataGridView1.GridColor),

                    backColorBrush = new SolidBrush(e.CellStyle.BackColor))

                ...{

                    using (Pen gridLinePen = new Pen(gridBrush))

                    ...{

                        // 擦除原单元格背景

                        e.Graphics.FillRectangle(backColorBrush, e.CellBounds);



                        if (e.Value.ToString() != this.dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex + 1].Value.ToString())

                        ...{



                            //右侧的线

                            e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1, e.CellBounds.Top,

                                e.CellBounds.Right - 1, e.CellBounds.Bottom - 1);

                            //绘制值

                            if (e.Value != null)

                            ...{

                                e.Graphics.DrawString((String)e.Value, e.CellStyle.Font,

                                    Brushes.Crimson, e.CellBounds.X + 2,

                                    e.CellBounds.Y + 2, StringFormat.GenericDefault);

                            }

                        }



                        //下边缘的线

                        e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1,

                                                    e.CellBounds.Right - 1, e.CellBounds.Bottom - 1);

                        e.Handled = true;

                    }

                }



            }



        }



        #endregion



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