Gridview checkbox is checked=false even when its been checked?

I have a gridview that is populated with a datatable and has an item template with a checkbox in it. Even when the checkbox is checked, the cs code says checked=false.

Asp:

     <asp:GridView ID="gvListOfPages" runat="server" AutoGenerateColumns="false" ShowHeader="false">
                        <Columns>  
                            <asp:TemplateField>
                                <ItemTemplate>
                                    <asp:CheckBox ID="chkPages" runat="server" />
                                </ItemTemplate>
                            </asp:TemplateField>
                            <asp:BoundField DataField="PageName" />                           
                        </Columns>
                    </asp:GridView>

C#:

 foreach (GridViewRow row in gvListOfPages.Rows)
    {
        System.Web.UI.WebControls.CheckBox chk = (System.Web.UI.WebControls.CheckBox)row.Cells[0].FindControl("chkPages");
        if (chk != null && chk.Checked)
        {
            int arrayIndex = Convert.ToInt32(chk.ID.Substring(chk.ID.Length - 1, chk.ID.Length));
        }
    }