popup window and parent value

    Hi
I have asp.net textbox and asp.net button, when I click I need to open up a new window calling gridview.aspx, and when select the commandfield, it should close the window and
get the value back of ID in the textbox from the parent window.

Any pointers pls suggest

gridview.aspx page                     <asp:GridView runat="server" AllowSorting="True"             AutoGenerateColumns="False" CellPadding="2" DataSourceID="SqlDataSource6"             BorderColor="#AAAAAA" BorderWidth="1px" Font-Size="XX-Small"             ForeColor="#333333&quo ...