定位行：
1.BindingSource.MoveLast()；
2.dataGridView1.FirstDisplayedScrollingRowIndex = dataGridView1.Rows. Count-1;
定位单元格：
1.dataGridView1.FirstDisplayedCell = dataGridView1.Rows[xxx].Cells[0];
2.dataGridView1.CurrentCell = dataGridView1.Rows[dataGridView1.Rows.Count-1].Cells[0];
dataGridView1.BeginEdit(true);