如何将Access Db中的数据添加到Treeview

Question

我在Access中有两个表：

客户

• 1）键（这是自动增量）
• 2）文本

订单

• 1）键
• 2）文本

• 3）Id_Customer

      OleDbConnection con = new OleDbConnection(strProvider);
      OleDbCommand cmd = new OleDbCommand(strSql, con);
      con.Open();
      OleDbDataReader dr = cmd.ExecuteReader();
      DataTable dtTree = new DataTable();
  
      int columnCount = dr.FieldCount;
  
      for (int i = 0; i < columnCount; i++)
      {
          dataGridView1.Columns.Add(dr.GetName(i).ToString(), dr.GetName(i).ToString());
      }
  
  
      string[] rowData = new string[columnCount];
       while (dr.Read())
       {
           for (int k = 0; k < columnCount; k++)
           {
               if (dr.GetFieldType(k).ToString() == "System.Int32")
               {
                   rowData[k] = dr.GetInt32(k).ToString();
               }
  
               if (dr.GetFieldType(k).ToString() == "System.String")
               {
                   rowData[k] = dr.GetString(k);
               }
           }
  
           dataGridView1.Rows.Add(rowData);
       }
  

如何将这些数据添加到Treeview中？