I have a button outside an update panel which controls an update panel very well. I also want another button to update this same update panel when the click event is triggered. How can I achieve this?
You can have multiple triggers registered to a single update panel. Something like the following should work:
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Button1" EventName="Click" />
<asp:AsyncPostBackTrigger ControlID="Button2" EventName="Click" />
</Triggers>
</asp:UpdatePanel>