下拉框控件

下拉框控件的一些设定：
 1             //市
 2             string strCity = WebLockConfig.Instance.webCom.GetCityByProId("");
 3             DataSet cityDS = Newtonsoft.Json.JsonConvert.DeserializeObject<DataSet>(strCity);
 4             cmbCity.Properties.DataSource = cityDS.Tables[0];
 5             cmbCity.Properties.DropDownRows = cityDS.Tables[0].Rows.Count;
 6             DataRow cityDR = cityDS.Tables[0].NewRow();
 7             cityDR["CITY_NAME"] = "请选择";
 8             cityDR["CITY_ID"] = "";
 9             cityDS.Tables[0].Rows.InsertAt(cityDR, 0);
10             cmbCity.SelectedText = "请选择";