Datagridview 虚拟模式

//把数据放到DataTable中
DataTable c_dtDtTble = null;
public DataTable GetDataSet()
  {
  SqlConnection conn = new SqlConnection(connectionString);
  SqlDataAdapter adapter = new SqlDataAdapter("SELECT * FROM Contact1", conn);
  ds = new DataSet();
  adapter.Fill(ds, "Contact1");
  c_dtDtTble=ds.Table[0];
  return c_dtDtTble ;
  }
//动态添加dataGridView列标题
private void Form1_Load(object sender, EventArgs e)
        {
                c_intColumnCount = c_dtDtTble1.Columns.Count;
                for (int i = 0; i < c_intColumnCount; i++)
                {
                    DataGridViewColumn l_dgvClmn = new DataGridViewTextBoxColumn();
                    l_dgvClmn.Name = c_dtDtTble1.Columns[i].ColumnName;
                    l_dgvClmn.HeaderText = c_dtDtTble1.Columns[i].ColumnName;
                    dgvContact2.Columns.Add(l_dgvClmn);
                }
        }
//填充单元格数据
private void dgvContact1_CellValueNeeded(object sender, DataGridViewCellValueEventArgs e)
        {
            e.Value = c_dtDtTble.Rows[e.RowIndex][e.ColumnIndex].ToString();
        }