合并Datagridview上多行列的值

public class MergedDataGridViewCell : DataGridViewTextBoxCell
{
    protected override void Paint(Graphics graphics, Rectangle clipBounds, Rectangle cellBounds, int rowIndex, DataGridViewElementStates cellState, object value, object formattedValue, string errorText, DataGridViewCellStyle cellStyle, DataGridViewAdvancedBorderStyle advancedBorderStyle, DataGridViewPaintParts paintParts)
    {
        // 获取相邻单元格的值
        string mergedValue = GetMergedValue(rowIndex);

        // 绘制合并后的值
        base.Paint(graphics, clipBounds, cellBounds, rowIndex, cellState, mergedValue, mergedValue, errorText, cellStyle, advancedBorderStyle, paintParts);
    }

    private string GetMergedValue(int rowIndex)
    {
        // 获取相邻单元格的值并合并为一个字符串
        // 这里根据实际情况进行处理，可以根据需要自定义合并逻辑
        string value1 = dataGridView.Rows[rowIndex].Cells[ColumnIndex - 1].Value.ToString();
        string value2 = dataGridView.Rows[rowIndex].Cells[ColumnIndex + 1].Value.ToString();
        return value1 + value2;
    }
}

private void dataGridView_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
{
    if (e.RowIndex >= 0 && e.ColumnIndex >= 0)
    {
        // 判断当前单元格是否需要合并
        if (NeedMerge(e.RowIndex, e.ColumnIndex))
        {
            e.PaintBackground(e.CellBounds, true);

            // 使用自定义的DataGridViewCell绘制
            MergedDataGridViewCell mergedCell = new MergedDataGridViewCell();
            mergedCell.InitializeEditingControl(e.RowIndex, null, null);
            mergedCell.Value = dataGridView.Rows[e.RowIndex].Cells[e.ColumnIndex].Value;
            mergedCell.Paint(e.Graphics, e.CellBounds, e.CellBounds, e.RowIndex, e.State, mergedCell.Value, mergedCell.FormattedValue, e.ErrorText, mergedCell.GetInheritedStyle(e.State), DataGridViewAdvancedBorderStyle.Single, DataGridViewPaintParts.All);

            e.Handled = true;
        }
    }
}

private bool NeedMerge(int rowIndex, int columnIndex)
{
    // 根据实际情况判断是否需要合并单元格
    // 这里可以根据需要自定义合并条件
    return dataGridView.Rows[rowIndex].Cells[columnIndex - 1].Value.ToString() == dataGridView.Rows[rowIndex].Cells[columnIndex + 1].Value.ToString();
}

private void dataGridView_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
{
    if (e.RowIndex >= 0 && e.ColumnIndex >= 0)
    {
        // 将需要合并的单元格的值设置为空
        if (NeedMerge(e.RowIndex, e.ColumnIndex))
        {
            e.Value = string.Empty;
            e.FormattingApplied = true;
        }
    }
}