ASP.NET

protected void btnSelect_Click(object sender, EventArgs e)
       {
           string selectedValue = Request.Form["radSelect"];
           int index = Convert.ToInt32(Request.Form["radSelect"]);
}

<asp:GridView ID="grdAll" runat="server" OnRowCommand="MPS_Selected" AutoGenerateColumns="false" OnRowDataBound = "grd_rowdatabound">
            <Columns>
                <asp:BoundField DataField="ID" HeaderText = "" Visible="false" />
                <asp:BoundField DataField="Name" HeaderText = "MPS Account Name" />
                <asp:BoundField DataField="Industry" HeaderText = "Industry" />
                <asp:BoundField DataField="SubIndustry" HeaderText = "Sub-Industry" />
                <asp:BoundField DataField="Geo" HeaderText = "Geo" />
                <asp:BoundField DataField="LocType" HeaderText = "Location" />
                <%--<asp:buttonfield buttontype="Button" commandname="Select" headertext="" text="Select"/>--%>
                <asp:TemplateField HeaderText="Select One">
                    <ItemTemplate>
                      <input  id="rdSelect" name= "radSelect" type="radio" value='<%# Eval("ID") %>' />
                      <%--<asp:RadioButton ID = "rdSelect" runat="server" onclick = "RadioCheck(this)" />
                      <asp:HiddenField ID="HiddenField1" runat="server" Value='<%#Eval("ID")%>' />--%>
                    </ItemTemplate>
                </asp:TemplateField>
            </Columns>

        </asp:GridView>