protected void ASPxGridView1_CustomCallback(object sender, DevExpress.Web.ASPxGridView.ASPxGridViewCustomCallbackEventArgs e) { if (e.Parameters == null) { return; } string[] param = e.Parameters.Split(';'); if (param.Length == 2 && param[0] == "customexpand") { ASPxGridView1.ExpandRow(Convert.ToInt32(param[1]), true); } }