if i am not wrong is this a solution that you were trying
DataSet ds = new DataSet();
DataTable dt = new DataTable();
dt.Columns.Add("Name");
dt.Rows.Add("Affan");
dt.Rows.Add("osama");
dt.Rows.Add("faraz");
dt.Rows.Add("saqib");
ds.Tables.Add(dt);
Session["AddDataTable"] = ds;
GridView1.DataSource = ((DataSet)Session["AddDataTable"]).Tables[0];
GridView1.DataBind();