private void CmbCity_SelectedIndexChanged(object sender, EventArgs e)
        {
            CmbDistrict.Items.Clear();

            SQLExecute excute = new SQLExecute();
            DataSet ds = new DataSet();
            int intCount = 0;

            ds = excute.GetDistrictByProvinceAndCity(CmbProvince.SelectedItem.ToString(),CmbCity.SelectedItem.ToString());
            intCount = ds.Tables[0].DefaultView.Count;

            for (int i = 0; i < intCount; i++)
            {
                CmbDistrict.Items.Add(ds.Tables[0].Rows[i][0].ToString());
            }
        }