自动递减行序列号

Question

您好，我有以下代码。 我希望删除我的Sno，即如果我删除Sno-4并且总Sno为5，则删除后Sno 5应该自动变为4

受保护的void grdTaskDetails_RowDeleting（对象发送者，DevExpress.Web.Data.ASPxDataDeletingEventArgs e）     {         字符串taskNo = Convert.ToString（lblPr.Text）; //更改唯一的密钥形式ID

    tbl_User usr = (tbl_User)Session["UserObj"];
    object NO = e.Values["Sno"]; //grid sno



    e.Cancel = true;
    try
    {
        decimal Sno = Convert.ToDecimal(NO);


        EzESSTblsDataContext tb = new EzESSTblsDataContext();


        //Change table name and parameter 
        var delete = (from n in tb.PurchaseReq_Grid_Temps
                      where n.CmpyCode == usr.CmpyCode && n.PRNo == lblPr.Text && n.Sno == Sno
                      select n).SingleOrDefault();

        if (delete != null)
        {
            try
            {

                tb.PurchaseReq_Grid_Temps.DeleteOnSubmit(delete);
                tb.SubmitChanges();
                FillGrid(usr.CmpyCode, taskNo);




            }
            catch
            {

            }
            finally
            {
                tb.Dispose();
            }
        }

    }
    catch
    {

    }

    grdTask.CancelEdit();

}