ASP.Net สงสัยเรื่อง update ข้อมูลจาก gridview ลง database ครับ

if(!Page.IsPostBack)
{
 // BindData
}

testlinq1DataContext db = new testlinq1DataContext();
        protected void Page_Load(object sender, EventArgs e)
        {

            if (!Page.IsPostBack)
            {
                show();
                
            }

            
        }
        private void show()
        {

            var ace = from a in db.ITdevicedetails

                      join b in db.Brands
                      on a.Specid equals b.Specid
                      join c in db.Devicestatus
                      on a.Statusid equals c.Statusid
                      where a.Statusid == "ST03"
                      join d in db.Typedevices
                      on a.Type equals d.Type


                      select new
                      {
                          IDdevice = a.IDdevice,
                          Type = d.Type,
                          Brand = b.Brand1,
                          Spec = b.Spec
                          ,
                          Model = b.Model,
                          Accode = a.Accode,
                          IPaddress = a.IPaddress,
                          Serialnumber = a.Serialnumber,
                          Status = c.Status,
                          Comment = a.Comment

                      };


            GridView1.DataSource = ace.ToList();
            GridView1.DataBind();
            
        }