Sorry for the answer to my own question, but I found a couple of ways to do this, and I thought that they could be useful for someone else.
, TypeConverter TypeConverterAttribute. : . .
, :
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="wbctrlstst._Default" %>
<%@ Register TagPrefix="x" TagName="TestControl" Src="~/TestControl.ascx" %>
<html xmlns="http://www.w3.org/1999/xhtml" >
<body>
<form id="form1" runat="server">
<div>
<x:TestControl runat="server" ID="testlist1">
<TestProperty X="1" Y="42" />
</x:TestControl>
</div>
</form>
</body>
</html>
, , , . PersistenceModeAttribute , , , , , .
[PersistenceMode(PersistenceMode.InnerProperty)]
public TestData TestProperty {
get {
return ViewState["TestProperty"] as TestData;
}
set {
ViewState["TestProperty"] = value;
}
}