Apologies if this is an old chestnut, but for some reason after several years of ASP.NET development I have only just found a reason to explore user controls (which I want to be able to create dynamically within placeholders and have properties which can be set at runtime). There seem to be a lot of threads on related subjects but many of them are very old and it is not at all clear what the current (3.5) position actually is.
I have implemented a trivial first test with the following ascx and code behind in the same folder as the page in which it is to be loaded:
<%@ Control Language="VB" AutoEventWireup="false" ClassName="Feedback" CodeFile="Feedback.ascx.vb" Inherits="FeedbackUC" %>
<asp:Label ID="lblMsg" runat="server" />
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