Multiple radiobutton without radiobuttonlist in gridview

storing Multiple selected radiobutton's of gridview?

 ASPX :

<asp:GridView ID="gvSurvey" runat="server" CellPadding = "4"  OnRowDataBound ="gvSurvey_RowDataBound" BorderWidth ="2"
AutoGenerateColumns="False" EmptyDataText="No data Available" GridLines="None"
HorizontalAlign="Center" ForeColor="#333333" Font-Names="Verdana" ShowFooter="True">
<RowStyle BackColor="White" />
<Columns>
<asp:BoundField DataField="HEADER" HeaderText="Description" ItemStyle-HorizontalAlign="Left"
FooterStyle-HorizontalAlign="Left" >
<ItemStyle HorizontalAlign="Left" />
</asp:BoundField>

<asp:TemplateField Visible="true" HeaderText ="Strongly Disagree">
<ItemTemplate>
<asp:RadioButton ID="rdbtn1" runat ="server" GroupName ="MyRadioGroup"/>

</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField Visible="true" HeaderText ="Agree">
<ItemTemplate>
  <asp:RadioButton ID="rdbtn2" runat ="server"  GroupName ="MyRadioGroup"/>
 
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField Visible="true" HeaderText ="Disagree">
<ItemTemplate>
  <asp:RadioButton ID="rdbtn3" runat ="server" GroupName ="MyRadioGroup"/>

</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField Visible="true" HeaderText ="Strongly Agree">
<ItemTemplate>
  <asp:RadioButton ID="rdbtn4" runat ="server"  GroupName ="MyRadioGroup"/>
   
</ItemTemplate>
</asp:TemplateField>
</Columns>
<FooterStyle BackColor="#507CD1" ForeColor="White" Font-Bold="True" />
<PagerStyle BackColor="#2461BF" ForeColor="White" HorizontalAlign="Center" />
<SelectedRowStyle BackColor="#D1DDF1" Font-Bold="True" ForeColor="#333333" />
<HeaderStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
<EditRowStyle BackColor="#2461BF" />
<AlternatingRowStyle BackColor="White" />
</asp:GridView>

 C# :

 for (i = 0; i < gvSurvey.Rows.Count; i++)
            {
                RadioButton rdbtn1 = (RadioButton)gvSurvey.Rows[i].Cells[3].FindControl("rdbtn1");
                RadioButton rdbtn2 = (RadioButton)gvSurvey.Rows[i].Cells[4].FindControl("rdbtn2");
                RadioButton rdbtn3 = (RadioButton)gvSurvey.Rows[i].Cells[5].FindControl("rdbtn3");
                RadioButton rdbtn4 = (RadioButton)gvSurvey.Rows[i].Cells[6].FindControl("rdbtn4");


          //      RadioButton rdbtn1=(RadioButton) gvSurvey.Rows[i].ClientID  

                qtn_no = dtSurvey.Rows[i]["QTN_NO"].ToString();
               

                if (rdbtn1.Checked)
                {
                    rdbtn1.Text = "1";
                    lblMsg.Text =  "You Procedure/insert query with parameters" .....
                }

                .... (Same for next 3 radiobuttons)

}