private void Gv_CellContentClick(object sender, DataGridViewCellEventArgs e)
 {
     try
     {
         DataGridView senderGrid = (DataGridView)sender;
         int          id         = Convert.ToInt32(gv.Rows[e.RowIndex].Cells[1].Value);
         if (senderGrid.Columns[e.ColumnIndex] is DataGridViewImageColumn && e.RowIndex >= 0)
         {
             var frm = new Form_MasterClassAddEdit
             {
                 customerClassId = id
             };
             if (frm.ShowDialog() == DialogResult.OK)
             {
                 Populate();
             }
         }
         if (senderGrid.Columns[e.ColumnIndex] is DataGridViewLinkColumn && e.RowIndex >= 0)
         {
             var customers = MasterClassController.GetCustomersByClass(id, "2020-01-24");
             var coll      = customers.Select(p => new
             {
                 p.CustomerCode,
                 p.CustomerName
             }).ToList();
             gvCustomer.DataSource = coll;
         }
     }
     catch (Exception ex)
     {
         MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
     }
 }
 private void BtnAdd_Click(object sender, System.EventArgs e)
 {
     try
     {
         var frm = new Form_MasterClassAddEdit
         {
             customerClassId = 0
         };
         if (frm.ShowDialog() == DialogResult.OK)
         {
             Populate();
         }
     }
     catch (Exception ex)
     {
         MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
     }
 }