怎么获取DataTable中的某一列的值？

DataTable.Columns[0].***

for (int i = 0; i < selectedCellCount; i++)
                    {
textBox7.Text = dataGridView2.SelectedCells[i].RowIndex.ToString(); //显示行
textBox8.Text = dataGridView2.SelectedCells[i].ColumnIndex.ToString(); //显示列
                        string x=dataGridView2.Rows[dataGridView2.SelectedCells[i].RowIndex].Cells[0].Value.ToString(); //行 AND 列
                    ｝

学习了！多谢！！