AFAIK a datagridview cannot bind to child properties.

Rick

Hi, I think you can bind child property in this view but I don't know
how to edit these property (in your problem)
This is the way: use Repeater (or DataList) and template
In your Visual Studo, open web page containning DataGridView (in Code
mode - not Design mode). May be your code like this

<asp:Repeater Id="companyGridView"
OnItemDataBound="companyGridView_ItemDataBound">
<HeaderTemplate><table><tr><td>Company</td></tr></HeaderTemplate>
<FooterTemplate></table></FooterTemplate>
<ItemTemplate>
<tr><td><asp:Label Text="<%# Eval("CompanyName") %>">
<asp:Repeater Id="addressGridView">
<HeaderTemplate><table><tr><td>Address</td></tr></HeaderTemplate>
<FooterTemplate></table></FooterTemplate>
<ItemTemplate>
<tr><td><asp:Label Text="<%# Eval("CompanyAddress") %>">
</td></tr>
</ItemTemplate>
</asp:Repeater>
</td></tr>
</ItemTemplate>
</asp:Repeater>

In your code behind:

protected void companyGridView_ItemDataBound(object sender,
RepeaterItemEventArgs e) {
    if( e.Item.ItemType == ItemType.Item || e.Item.ItemType ==
ItemType.AlternatingItem) {
       Company boundObj = e.Item.DataItem as Company; // your Company
object which is binding
    Repeater rpt = e.Item.FindControl("addressGridView") as Repeater; //
ger reference
    rpt.DataSource = Companay.Address; // Address must be a boundable
object (sorry if I don't use this term exactly)  (IList, IEnumberable,
DataTable, ..)
    rpt.DataBind();
}
}

The important thing is ItemDataBound event, you registter that event and
do anything you want