binding a list within a list to gridview

[janaki thakur]

Hello ,

I have the following code:

public class abc
{
public string customername { get; set; }
public List<def> DEF { get; set; }
}


public class def
{
public string materialcode { get; set; }
}

on page load 

protected void Page_Load(object sender, EventArgs e)
{
List<abc> test1 = new List<abc>();
List<def> test2 = new List<def>();

test2.Add(new def() {materialcode="something" });
test1.Add(new abc(){customername="anything", DEF=test2});
GridView1.DataSource = test1;
GridView1.DataBind();
}

and in the ascx file

<asp:GridView ID="GridView1" runat="server">

<Columns>
<asp:TemplateField HeaderText="Charge Code">
<ItemTemplate>
<asp:Label ID="lblchargecode" runat="server" Text='<%#((def)Eval("DEF"))[0].materialcode %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>

</Columns>
</asp:GridView>

I am getting an error message stating that def is not a member , if i am missing an assembly reference.

Please help me bind it to the gridview. Its very urgent

Thanks all.

[samueal]

Where the error is? Give a different name for class def