Repeater绑定dictionary数据源代码及报错解决

<asp:repeater id="repeater1" runat="server">
<itemtemplate>
<%# ((keyvaluepair<int, list<user>>)container.dataitem).key %> <br />
<asp:repeater id="repeater2" runat="server" datasource='<%# ((keyvaluepair<int, list<user>>)container.dataitem).value %>'>
<itemtemplate>
<%# (container.dataitem as user).id %>
<%# (container.dataitem as user).name %>
</itemtemplate>
</asp:repeater>
<hr />
</itemtemplate>
</asp:repeater>

public partial class temp : system.web.ui.page
{
dictionary<int, list<user>> dict = new dictionary<int, list<user>>();
protected void page_load(object sender, eventargs e)
{
dict.add(1, new list<user>
{
new user{id = 1, name = "aa"}
,new user{id = 2, name = "bb"}
});
dict.add(2, new list<user>
{
new user{id = 3, name = "cc"}
,new user{id = 4, name = "dd"}
});
repeater1.datasource = dict;
repeater1.databind();
}
}
public class user
{
public int id{get;set;}
public string name{get;set;}
}