Gridview中TemplateField中的复选框在回发时丢失选中状态

我有一个带有模板字段的gridview。该模板字段中有一个复选框。我在gridview外有一个submit按钮,用于分配已检查的记录。在回发上,没有复选框注册为正在选中。这是我的密码:

<Columns>
                <asp:TemplateField>
                    <ItemTemplate>
                        <asp:CheckBox ID="cb" Checked="false" runat="server" />
                        <asp:Label ID="lblCFID" runat="server" Visible="false" Text='<%# Eval("ID") %>' />
                    </ItemTemplate>
                </asp:TemplateField>
                <asp:BoundField HeaderStyle-HorizontalAlign="Center" DataField="Name" HeaderText="Name" />
                <asp:BoundField HeaderStyle-HorizontalAlign="Center" DataField="DOB" HeaderText="Date of Birth" />
                <asp:BoundField HeaderStyle-HorizontalAlign="Center" HeaderText="Gender" DataField="Gender"  />
                <asp:BoundField HeaderStyle-HorizontalAlign="Center" HeaderText="Status" DataField="Status"  />
                <asp:BoundField HeaderStyle-HorizontalAlign="Center" HeaderText="Plan Name" DataField="PlanName"  />
                <asp:BoundField HeaderStyle-HorizontalAlign="Center" HeaderText="Type" DataField="ControlType"  />
                <asp:BoundField HeaderStyle-HorizontalAlign="Center" HeaderText="Date of Service" dataformatstring="{0:MMMM d, yyyy}" htmlencode="false" DataField="DateofService"  />
            </Columns>

protected void AssignRecords(object sender, EventArgs e)
{
    int Rows = gvASH.Rows.Count;
    for (int i = 0; i < Rows; i++)
    {
        //CheckBoxField cb = ((CheckBoxField)gvASH.Rows[i].Cells[1]).;
        CheckBox cb = (CheckBox)gvASH.Rows[i].Cells[0].FindControl("cb");
        Label lblID = (Label)gvASH.Rows[i].Cells[0].FindControl("lblCFID");
        if (cb.Checked == true)
        {

            string ID = lblID.Text;
            //Assign Code
        }
    }
}

我在字符串ID=lblID.Text上设置了一个断点;但它从未找到任何被检查过的。