ASP.NET

<div id="resultList">
    <asp:ListView ID="lstResults" runat="server">
        <LayoutTemplate>
            <table id="Table1" runat="server" class="TableCSS">
                <tr id="Tr1" runat="server" class="TableHeader">
                    <td id="Td1" runat="server">
                        Merchant Name
                    </td>
                </tr>
                <tr id="ItemPlaceholder" runat="server">
                </tr>
            </table>
        </LayoutTemplate>
        <ItemTemplate>
            <tr class="ItemCSS">
                <td>
                    <asp:Label ID="Label1" runat="server" Text='<%# Eval("Title")%>'>
                    </asp:Label>
                </td>
            </tr>
        </ItemTemplate>
    </asp:ListView>
</div>

private void loadList()
{
    categoryID = (int)Session["categoryID"];
    zipCode = Session["zipCode"].ToString();

    merchants = TDCBizObj.GetMerchantsByQuery(categoryID, zipCode);

    lstResults.DataSource = merchants;
    lstResults.DataBind();
}

void Page_Load()
{
    if(!Page.IsPostBack)
    {
       Session["something"] = true
    }
}
void Page_LoadComplete()
{
     //i need this value between postbacks, but dont want to init it every time
     bool something = Session["something"] as bool;
}
/*
i would like to have something like this
void Page_IsChangedOrRedirected()
{
     Session["something"] = null;
}
*/

myVar.dateredeemed = DateTime.Parse("2010-12-03"); //still throws the same error
myVar.dateredeemed = (DateTime?)dateTime; //still throws the same error
myVar.dateredeemed = DateTime.Now; //still throws the same error