例如下面这个方法，得到了一个视图的数据包含了省份城市店铺

public DataSet GetData()        {            try            {                StringBuilder sql = new StringBuilder("SELECT PROVINCE_ID,PROVINCE_NAME,CITY_ID,CITY_NAME,DEALER_ID,DEALER_NAME ");                sql.Append(" FROM VIEW_P_C_Data  ");                sql.Append(" WHERE  1=1 order by PROVINCE_NAME,CITY_NAME");                DataSet ds = dbManager.Query(sql.ToString());                return ds;            }            catch (Exception ex)            {                throw new Exception(ex.Message);            }        }

首先获取到数据DataSet ds = GetData();

声明：HashSet<string> vehicle_p = new HashSet<string>();

然后循环ds

foreach (DataRow row in ds.Tables[0].Rows)

{

}

循环里做一个复制判断，因为省份是重复的，城市也是。一对多的关系。所以不同城市相同省份时，对于json结构只要添加一次省份

bool exist_province = vehicle_p.Add(row["PROVINCE_NAME"].ToString());

bool exist_city = vehicle_p.Add(row["CITY_ID"].ToString());

//当省份不存在时，第一次添加

if (exist_province)

{

}else{

//相同省份不同城市时，

if (exist_city)

{

}else{

//相同城市，不同店铺时

}

}

 

PS：全部代码

public List
     
       GetAllDealer()        {            List
      
        list = new List
       
        ();            DataSet ds = GetData();            HashSet
        
          vehicle_p = new HashSet
         
          ();            Text_Drive_Dealer t_dealer = null;            List
          
            list_vm = null; Text_City vm = null; foreach (DataRow row in ds.Tables[0].Rows) { bool exist_province = vehicle_p.Add(row["PROVINCE_NAME"].ToString()); bool exist_city = vehicle_p.Add(row["CITY_ID"].ToString()); if (exist_province) { //当省份不存在时，第一次添加 t_dealer = new Text_Drive_Dealer(); t_dealer.ProvinceID = row["PROVINCE_ID"].ToString(); t_dealer.ProvinceName = row["PROVINCE_NAME"].ToString(); //第一次添加城市 vm = new Text_City(); vm.CityID = row["CITY_ID"].ToString(); vm.CityName = row["CITY_NAME"].ToString(); //第一次添加该城市的特约店 Text_dealer td = new Text_dealer(); td.DealerID= row["DEALER_ID"].ToString(); td.DealerName = row["DEALER_NAME"].ToString(); List
           
             list_td = new List
            
             (); list_td.Add(td); vm.text_dealer = list_td; list_vm = new List
             
              (); list_vm.Add(vm); t_dealer.TextDrive_City = list_vm; list.Add(t_dealer); } else { if (exist_city) { //第一次添加城市跟特约店 vm = new Text_City(); vm.CityID = row["CITY_ID"].ToString(); vm.CityName = row["CITY_NAME"].ToString(); Text_dealer td = new Text_dealer(); td.DealerID = row["DEALER_ID"].ToString(); td.DealerName = row["DEALER_NAME"].ToString(); List
              
                list_td = new List
               
                (); list_td.Add(td); vm.text_dealer = list_td; t_dealer.TextDrive_City.Add(vm); } else { //已有城市，添加特约店 //Text_City vm = new Text_City(); Text_dealer td = new Text_dealer(); td.DealerID = row["DEALER_ID"].ToString(); td.DealerName = row["DEALER_NAME"].ToString(); vm.text_dealer.Add(td); //t_dealer.TextDrive_City.Find().text_dealer=; } } } return list; }