Dapper关联查询
1、一对一:
using (IDbConnection connecton = new MySqlConnection(ConfigurationManager.ConnectionStrings["default"].ConnectionString)) { string sql = @"SELECT * from expand_userbasicinformation b JOIN expand_users u on b.UserId = u.UserId"; var infos = connecton.Query<UserInfo, User, UserInfo>(sql, (info, user) => { info.User = user; return info; }, splitOn: "UserId"); }
其中,实体定义如下:
public class UserInfo { public string InformationId { get; set; } public string UserId { get; set; } public User User { get; set; } public string RealName { get; set; } } public class User { public string UserId { get; set; } public string LoginName { get; set; } public string LoginPassword { get; set; } }
2、一对多:
using (IDbConnection connecton = new MySqlConnection(ConfigurationManager.ConnectionStrings["crmcontroller"].ConnectionString)) { List<Client> clients = new List<Client>(); string sql = @"SELECT * from crm_client_list join crm_client_field_value on ClientId = ModelId"; var infos = connecton.Query<Client, ClientField, Client>(sql, (c, f) => { var currentClient = clients.Find(x => x.ClientId == c.ClientId); if (currentClient == null) { c.Fields.Add(f); clients.Add(c); return c; } else { currentClient.Fields.Add(f); return currentClient; } }, splitOn: "ModelId"); }
其中,实体定义如下:
public class Client { public Client() { this.Fields = new List<ClientField>(); } public string ClientId { get; set; } public string Name { get; set; } public string PhoneNumber { get; set; } public string IDNumber { get; set; } public List<ClientField> Fields { get; private set; } } public class ClientField { public string FieldValueId { get; set; } public string ModelId { get; set; } public string FieldId { get; set; } public string FieldValue { get; set; } }
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