ASPX
Here, I have not written the complete GridView Tag :
--
<gridview>
<Columns>
<asp:TemplateField HeaderText="Select">
<ItemTemplate>
<asp:RadioButton ID="Rdbttn_Package" runat="server" AutoPostBack="true" Text='<%# DataBinder.Eval(Container,"DataItem.RP_SHORT_DESC") %>'
ToolTip='<%# DataBinder.Eval(Container,"DataItem.RP_AMOUNT") %>' OnCheckedChanged="Rdbttn_Package_CheckedChanged" />
</ItemTemplate>
<HeaderStyle HorizontalAlign="Right" />
</asp:TemplateField>
</Columns>
<GridView>
VB.NET
Dim rb As New RadioButton
Dim rbNewSelect As New RadioButton
Dim strOldSelect As String
Lbl_Error.Text = String.Empty
rbNewSelect = CType(sender, RadioButton)
For Each gvRow As GridViewRow In gv_RenewalSchemePackage.Rows
rb = CType(gvRow.FindControl("Rdbttn_Package"), RadioButton)
If (rb.Checked = True And rb.UniqueID <> rbNewSelect.UniqueID) Then
strOldSelect = rb.UniqueID
rbNewSelect.Checked = True
''Additional Code paste here
Catch ex As Exception
Lbl_Error.Text = "Error :" & ex.Message
Finally
End Try