<div>
            <asp:GridView ID="PropertyGridView" runat="server" AutoGenerateColumns="False" DataSourceID="PropertyObjectDataSource"
                DataKeyNames="ID" OnRowCreated="PropertyGridView_RowCreated" OnPreRender="PropertyGridView_PreRender">
                <Columns>
                    <asp:TemplateField>
                        <ItemTemplate>
                            <asp:CheckBox runat="server" ID="myCheckBox" Checked='<%# Bind("IsRequired") %>' />
                        </ItemTemplate>
                    </asp:TemplateField>
                    <asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name" />
                    <asp:BoundField DataField="Description" HeaderText="Description" SortExpression="Description" />
                    <asp:BoundField DataField="Value" HeaderText="Value" SortExpression="Value" />
                    <asp:BoundField DataField="Type" HeaderText="Type" ReadOnly="True" SortExpression="Type" />
                </Columns>
            </asp:GridView>
            <asp:ObjectDataSource ID="PropertyObjectDataSource" runat="server" SelectMethod="GetProperties"
                TypeName="Giada.TP.Manager.KindPropertyManager"></asp:ObjectDataSource>
            <asp:Button ID="Button1" runat="server" Text="Button" />
        </div>

private Collection<CheckBox> checkBoxCollection = new Collection<CheckBox>();

    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void PropertyGridView_RowCreated(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {

            checkBoxCollection.Add((CheckBox)e.Row.FindControl("myCheckBox"));
           
        }
    }

    protected void PropertyGridView_PreRender(object sender, EventArgs e)
    {
        foreach (CheckBox c in checkBoxCollection)
        {
            Response.Write(string.Format("il valore di {0} è:{1}</br>",c.ClientID,c.Checked));
        }

    }