Way To Use VS 2005 Gridview Delete Button With Datasource Markup

using gridview delete button with datasource markup:
source Code:

<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:direct_deliveryConnectionString %>"
SelectCommand="select pk_ddlvryDetailID,fk_grfdetailID,itemDescription,qty,uom,rate,(qty*rate) as Amount
from qddlvrydetails
where fk_ddlvryMasterID=@id"
DeleteCommand="delete
from tblddlvrydetails
where pk_ddlvrydetailid=@id">
[code]...
I created a parameter named @ID which will received value from grid selectedvalue whenever the delete button fire up but whenever i do that the will just postback without delete the row.