Edit,update,delete inside datagridview ,windows application C#

SqlConnection myConnection = new SqlConnection();
//now you can set ConnectionString property for myConnection
myConnection.ConnectionString = ConfigurationSettings.AppSettings["myConnectionString"];
try
{
    for (int i = 0; i < dataGridView1.Rows.Count; i++)
    {
        if (Convert.ToInt32(dataGridView1.Rows[i].Cells["select"].Value) == 1)
        {
            if (dataGridView1.Rows.Count != null)
            {
                if (dataGridView1.Rows.Count > 0)
                {
                    DialogResult result = MessageBox.Show("Are you sure you want to proceed in Updation ?", "Confirmation", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
                    if (result == DialogResult.Yes)
                    {

                        string aa = dataGridView1.Rows[i].Cells["id"].Value.ToString();
                        string sms_policy = dataGridView1.Rows[i].Cells["smspolicyDataGridViewTextBoxColumn"].Value.ToString();
                        string income = dataGridView1.Rows[i].Cells["incomeDataGridViewTextBoxColumn"].Value.ToString();
                        string ratio = dataGridView1.Rows[i].Cells["ratioDataGridViewTextBoxColumn"].Value.ToString();
                        string payment = dataGridView1.Rows[i].Cells["paymentDataGridViewTextBoxColumn"].Value.ToString();
                        string feature = dataGridView1.Rows[i].Cells["featureDataGridViewTextBoxColumn"].Value.ToString();
                        string description = dataGridView1.Rows[i].Cells["descriptionDataGridViewTextBoxColumn"].Value.ToString();


                        SqlCommand cmd = new SqlCommand();
                        cmd.CommandText = "update sms set  sms_policy='" + sms_policy + "',income='" + income + "',ratio='" + ratio + "',payment='" + payment + "',feature='" + feature + "',description='" + description + "'  where id='" + aa + "'";

                        cmd.Connection = myConnection;
                        myConnection.Open();
                        cmd.ExecuteNonQuery();
                        myConnection.Close();
                        Rebind();
                        MessageBox.Show("Update Record Success Folly");



                    }
                }
            }
        }
    }
}

catch (Exception a)
{
    MessageBox.Show("Server Have Technical problem Try After Some Time ");
}