This.bind()只使用第一个数据集，而不是第二个数据集

我有一个问题，我想绑定一个数据集与aspx形式的标签从后面的代码，我在一个函数中使用2个数据集，但问题是，它是绑定第一个数据集只。

我的代码是这样的:

 private void fill()
    {
        DateTime dat;
        if (txtDate.Text == "")
            dat = DateTime.Now;
        else
            dat = DateTime.ParseExact(txtDate .Text , "M/d/yyyy", null);
        rtbl.LoadRoomTypes(_ds, SessionContext.PropertyID,dat);
        dlDashBoard.DataSource = _ds.Tables[rtbl.SqlEntityX];
        dlDashBoard.DataBind();
        foreach(DataListItem item in dlDashBoard .Items )
        {
            BindNestedItem(item.ItemIndex );

        }
        _ds = null;
        RoomTypeBAL rtbl1 = new RoomTypeBAL(0);

        rtbl1.LoadTotalFree(_ds3, SessionContext.PropertyID, dat);
        if(_ds3 !=null && _ds3.Tables[rtbl1 .SqlEntityX ].Rows.Count >0)
        this.DataBind();//Problem is here binding _ds always but I want to bind _ds3
    }

我的来源是这样的:

<table>
   <tr>
                <td>
                    <asp:Label ID="Label1" runat="server" Text="FreeRooms :"></asp:Label>
                </td>
                <td>
                    <asp:Label ID="lblfreeRoom1" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tfreeroom1"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="lblfreeRoom2" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tfreeroom2"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="lblfreeRoom3" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tfreeroom3"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="lblfreeRoom4" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tfreeroom4"].ToString()%>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="lblfreeRoom5" runat="server" Text='<%#_ds3.Tables[0].Rows[0]["tfreeroom5"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="lblfreeRoom6" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tfreeroom6"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="Label2" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tfreeroom7"].ToString() %>'></asp:Label>
                </td>
            </tr>
            <tr>
                <td>
                    <asp:Label ID="Label3" runat="server" Text="Arrivals :"></asp:Label>
                </td>
                <td>
                    <asp:Label ID="Label4" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tarrival1"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="Label5" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tarrival2"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="Label6" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tarrival3"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="Label7" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tarrival4"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="Label8" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tarrival5"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="Label9" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tarrival6"].ToString() %>'></asp:Label>
                </td>
                <td>
                    <asp:Label ID="Label10" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tarrival7"].ToString() %>'></asp:Label>
                </td>
            </tr>
    <tr>
        <td>
            <asp:Label ID="Label11" runat="server" Text="CheckOuts :"></asp:Label>
        </td>
        <td>
            <asp:Label ID="Label12" runat="server" Text='<%# _ds3.Tables[0].Rows[0]["tcheckout1"].ToString()%>'></asp:Label>
        </td>
        <td>
            <asp:Label ID="Label13" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tcheckout2"].ToString() %>'></asp:Label>
        </td>
        <td>
            <asp:Label ID="Label14" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tcheckout3"].ToString() %>'></asp:Label>
        </td>
        <td>
            <asp:Label ID="Label15" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tcheckout4"].ToString() %>'></asp:Label>
        </td>
        <td>
            <asp:Label ID="Label16" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tcheckout5"].ToString() %>'></asp:Label>
        </td>
        <td>
            <asp:Label ID="Label17" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tcheckout6"].ToString() %>'></asp:Label>
        </td>
        <td>
            <asp:Label ID="Label18" runat="server" Text='<%#  _ds3.Tables[0].Rows[0]["tcheckout7"].ToString() %>'></asp:Label>
        </td>
    </tr>
</table>

if(_ds3 !=null && _ds3.Tables[rtbl1 .SqlEntityX ].Rows.Count >0)
dlDashBoard.DataSource = _ds3.Tables[rtbl.SqlEntityX];
dlDashBoard.DataBind();