Всем здрям!

Я добавляю некий ascx контрол в UpdatePanel и затем этот UpdatePanel на aspx страницу.

          UpdatePanel up = new UpdatePanel();
          cell.Controls.Add(up);
...

            SelectVendorControl selectVendor =
              (SelectVendorControl)LoadControl("~/Controls/SelectVendorControl.ascx");
            selectVendor.ID = "selectVendor" + oi.oi.OrderItemId.ToString();
            selectVendor.Visible = false;
            selectVendor.SaveCloseButton.Click += new EventHandler(SaveCloseButton_Click);
            selectVendor.CancelButton.Click += new EventHandler(CancelButton_Click);
            selectVendor.SaveCloseButton.CommandArgument = btn.CommandArgument;
            up.ContentTemplateContainer.Controls.Add(selectVendor);

Проблема в том когда я пытаюсь выбрать какой-либо Item из SelectVendorControl.ascx, выбор происходит очень медленно (примерно 1 сек).

Фрагмент SelectVendorControl.ascx:

<%@ Control Language="C#" AutoEventWireup="true" CodeBehind="SelectVendorControl.ascx.cs"
    Inherits="ToolsTH.Controls.SelectVendorControl" %>
<fieldset>
    <legend>Vendors</legend>
    <div style="padding: 5px; width: 300px; overflow: auto; height: 200px;">
        <asp:DataList ID="dlVendors" runat="server" OnItemCommand="dlVendors_ItemCommand"
            OnItemDataBound="dlVendors_ItemDataBound" Width="100%" BorderStyle="None">
            <HeaderTemplate>
            </HeaderTemplate>
            <ItemTemplate>
                <table id="tb" cellpadding="0" cellspacing="0" border="0" style="border-collapse: collapse">
                <tr id="trRow" runat="server">
                    <td width="100%" id="td1" runat="server">
                    <!--
                        <asp:LinkButton ID="LinkButton1" CommandArgument='<%# Eval("VendorID").ToString() %>'
                            runat="server"><%# Eval("VendorName") %></asp:LinkButton>
                            -->
                        <asp:LinkButton ID="LinkButton2" CommandArgument='123' runat="server"><%# "Hkkjh" %>
                        </asp:LinkButton>
                    </td>
                    <td align="right" id="td3" runat="server">
                    <!--
                      <%# (Eval("Quantity") != null) ? (Eval("Quantity")).ToString() + "-" : ""%>
                      -->
                    </td>
                    <td align="right" id="td2" runat="server">
                    <!--
                        <%# (Eval("Cost") != null) ? ((decimal)Eval("Cost")).ToString("c") + "-": ""%>
                        -->
                    </td>
                    <td align="right" id="td4" runat="server">
                    <!--
                        <%# (Eval("CostSource") != null) ? Eval("CostSource").ToString().Substring(0, 1) : ""%>
                        -->
                    </td>
                    <td align="right" id="td5" runat="server">
                    <!-- Adding item existing status in db -->
                    </td>
                </tr>
                </table>
            </ItemTemplate>
            <FooterTemplate>
            </FooterTemplate>
        </asp:DataList>
    </div>
</fieldset>
<table>
    <tr>
        <td>
            <fieldset>
                <legend>Shipping</legend>
                <asp:DropDownList ID="dlShippingMethod" runat="server">
                </asp:DropDownList>
            </fieldset>
        </td>
        <td>
            <fieldset>
                <legend>Cost</legend>
                <asp:TextBox ID="tbCost" runat="server" Width="100px"></asp:TextBox>
            </fieldset>
        </td>
        <td>
            <fieldset>
                <legend>Shipping Cost</legend>
                <asp:TextBox ID="tbShippingCost" runat="server" Width="100px"></asp:TextBox>
            </fieldset>
        </td>
    </tr>
</table>
<fieldset>    
    <legend>Vendor Notes</legend>
    <asp:TextBox ID="tbVendorNotes" runat="server" TextMode="MultiLine" Width="100%"></asp:TextBox>
</fieldset>
<fieldset style="display: none">
    <legend>Submit Method </legend>
    <asp:RadioButton ID="RadioButton1" runat="server" Text="API" />
    <asp:RadioButton ID="RadioButton2" runat="server" Text="Email" />
</fieldset>
<br />
<asp:Button ID="btnSaveClose" runat="server" Text="Save &amp; Close" Width="50%" />&nbsp;<asp:Button
    ID="btnCancel" runat="server" Text="Cancel" />

Заранее благодарен.