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 private void button65_Click(object sender, EventArgs e)
        {

            Int32 selectedCellCount =  dataGridView5.GetCellCount(DataGridViewElementStates.Selected);
            MessageBox.Show(selectedCellCount.ToString());
            if (selectedCellCount > 0)
            {
                if (dataGridView1.AreAllCellsSelected(true))
                {
                    MessageBox.Show("All cells are selected", "Selected Cells");
                }
                else
                {
                    System.Text.StringBuilder sb =
                        new System.Text.StringBuilder();

                    for (int i = 0;
                        i < selectedCellCount; i++)
                    {
                        sb.Append("Row: ");
                        sb.Append(dataGridView1.SelectedCells[i].RowIndex
                            .ToString());
                        sb.Append(", Column: ");
                        sb.Append(dataGridView1.SelectedCells[i].ColumnIndex
                            .ToString());
                        sb.Append(Environment.NewLine);
                    }

                    sb.Append("Total: " + selectedCellCount.ToString());
                    MessageBox.Show(sb.ToString(), "Selected Cells");
                }
            }
        }