private void btnDelete_Click(object sender, EventArgs e) { if (rowindex > -1) { DialogResult result = MessageBox.Show("Are you sure you want to permanently delete this?", "Delete Appoinment", MessageBoxButtons.YesNo, MessageBoxIcon.Warning); if (result == DialogResult.Yes) { c.contactId = int.Parse(txtCntID.Text); bool isSuccess = c.delete(c); if (isSuccess == true) { MessageBox.Show("Contact Successfully Deleted "); clear(); } else { MessageBox.Show("Faild to Deleted Contact try again"); } } } rowindex = -1; //load data table DataTable dt = c.Select(); dgvContact.DataSource = dt; }