String autoString="自动添加";
private void dataGridView1_RowsAdded(object sender, DataGridViewRowsAddedEventArgs e)
{
if (dataGridView1.Rows.Count - 1 >DT.Rows.Count )
{
dataGridView1.Rows[dataGridView1.SelectedCells[0].RowIndex].Cells[2].Value = autoString;
}
}