单击按钮后会话值丢失

Question

我使用会话来保存哈希表。它有不同的键值对，有些键引用'List'对象。

我在转发器控件中有不同的按钮来更改List的值，然后将其放回到哈希表中。然后使用相同的会话来保存该哈希表。但有时候会议中的变化会丢失。不知道为什么。我试过我的测试服务器。它可以正常工作。在Prod服务器上，我遇到了这个问题。

有什么建议吗？

<asp:Repeater ID="rptCountry" runat="server" OnItemDataBound="rptCountry_ItemDataBound" OnItemCommand="rptCountry_ItemCommand">
        <ItemTemplate>
                <asp:Button ID="btnCountry" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "Country").ToString() %>' CssClass="iButton Disabled" Enabled="false" UseSubmitBehavior="False" CommandName="Select" />
                <asp:Label ID="hdnCountryCode" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "CountryCode")%>' Visible="false" />
        </ItemTemplate>
</asp:Repeater>

protected void rptCountry_ItemCommand(object sender, RepeaterCommandEventArgs e)
{
if (e.CommandName.Equals("Select"))
        {
            Button btnCountry = (Button)e.Item.FindControl("btnCountry");
            Label hdnCountryCode = (Label)e.Item.FindControl("hdnCountryCode");

            if (Session["SearchFilter"] != null)
            {
                Hashtable htSearchFilter = (Hashtable)Session["SearchFilter"];
                List<string> countries = (List<string>)htSearchFilter["Country"];
                if (countries != null && countries.Count > 0)
                {
                    bool countriesExists = false;
                    foreach (string country in countries)
                    {
                        if (country.Equals(hdnCountryCode.Text.Trim()))
                        {
                            countriesExists = true;
                        }
                    }
                    if (!countriesExists)
                    {
                        countries.Add(hdnCountryCode.Text.Trim());
                        btnCountry.CssClass = "iButton Active";
                    }
                    else
                    {
                        countries.Remove(hdnCountryCode.Text.Trim());
                        btnCountry.CssClass = "iButton";
                    }
                }
                else
                {
                    countries.Add(hdnCountryCode.Text.Trim());
                    btnCountry.CssClass = "iButton Active";
                }

                htSearchFilter["Country"] = countries;
                Session["SearchFilter"] = htSearchFilter;
                ProvinceReloadControl(countries);
            }
        }

        InitControl();
}