public void SqlDEPTTree_NodeSelected( 
  TreeNode node = tree.SelectedNode; 
  if (node != null) 
  { 
   try 
   { 
     CFSQLConnect(); 
     OleDbCommand cmd = CFSConn.CreateCommand(); 
     cmd.CommandText = "select D_ID,D_BName,D_KName from Tb_Dept where D_KName='" + node.Text + "'"; 
     OleDbDataReader myread = cmd.ExecuteReader(); 
     if (myread.Read()) 
     { 
       Datagridview1[i,j]= myread["D_ID"].ToString(); 
             ...... 
             ...... 
     } 
     CFSConn.Close(); 
     cmd.Dispose(); 
     myread.Dispose(); 
    } 
    catch (Exception ex) 
    { 
       MessageBox.Show(ex.Message); 
    } 
   } 
 }