Asp.Net2.0 如何設定 GridView 合并行或列？

    this.GridView1.DataSource = dt;
        this.GridView1.DataBind();

//********************************************* 在資料繫結之前進行判斷
        TableCell oldTc = GridView1.Rows[0].Cells[0];
        for (int i = 1; i < GridView1.Rows.Count; i++)
        {                     
            TableCell tc = GridView1.Rows[i].Cells[0];   
            if (oldTc.Text == tc.Text)
            {
                tc.Visible = false;
                if (oldTc.RowSpan == 0)
                {
                    oldTc.RowSpan = 1;
                }
                oldTc.RowSpan++;
                oldTc.VerticalAlign = VerticalAlign.Middle;           

            }
            else
            {
                oldTc = tc;
            }
        }

//**************************************  aspx 頁面。

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" OnRowCreated="GridView1_RowCreated"  >
             <Columns>
                 <asp:BoundField DataField="類別" HeaderText="類別" >
                      <itemstyle cssclass="nameA" HorizontalAlign=Center  Width="130px" />
                 </asp:BoundField>              
              
        </Columns>
        </asp:GridView>

//註：合并列用繫結資料行。