private void buttonADD_Click(object sender, EventArgs e)
 {
     using (AddEdit_TheatreForm frm = new AddEdit_TheatreForm(null, 0))
     {
         if (frm.ShowDialog() == DialogResult.OK)
         {
             tHEATREBOOKBindingSource.DataSource = db.THEATREBOOKs.ToList();
         }
     }
 }
 private void dgvTheatre_DoubleClick(object sender, EventArgs e)
 {
     model.TID = Convert.ToInt32(dgvTheatre.CurrentRow.Cells["TID"].Value);
     using (AddEdit_TheatreForm frm = new AddEdit_TheatreForm(tHEATREBOOKBindingSource.Current as THEATREBOOK, model.TID))
     {
         if (frm.ShowDialog() == DialogResult.OK)
         {
             tHEATREBOOKBindingSource.DataSource = db.THEATREBOOKs.ToList();
         }
     }
 }