Controls :: ITextSharp - Register For EventValidation Can Only Be Called During Render

How to convert to pdf it is displaying error RegisterForEventValidation can only be called during Render();
 
 <asp:DataList ID="DataList1" runat="server">
<ItemTemplate><br />
<asp:Label ID="Label1" runat="server" Text='<%# bind("question") %>'></asp:Label><br />
<asp:RadioButton ID="RadioButton1" runat="server" Text='<%# bind("answer1") %>' /><br />
<asp:RadioButton ID="RadioButton2" runat="server" Text='<%# bind("answer2") %>' /><br />
<asp:RadioButton ID="RadioButton3" runat="server" Text='<%# bind("answer3") %>' /><br />
<asp:RadioButton ID="RadioButton4" runat="server" Text='<%# bind("answer4") %>' />
</ItemTemplate></asp:DataList></div>