using SqlSugar; using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace OrmTest { public class UCustom012 { public static void Init() { var db = NewUnitTest.Db; db.CodeFirst.InitTables(); db.DbMaintenance.TruncateTable(); db.DbMaintenance.TruncateTable(); db.DbMaintenance.TruncateTable(); db.Insertable(new RoomA() { RoomId = 1, RoomName = "北大001室", SchoolId = 1 }).ExecuteCommand(); db.Insertable(new RoomA() { RoomId = 2, RoomName = "北大002室", SchoolId = 1 }).ExecuteCommand(); db.Insertable(new RoomA() { RoomId = 3, RoomName = "北大003室", SchoolId = 1 }).ExecuteCommand(); db.Insertable(new RoomA() { RoomId = 4, RoomName = "清华001厅", SchoolId = 2 }).ExecuteCommand(); db.Insertable(new RoomA() { RoomId = 5, RoomName = "清华002厅", SchoolId = 2 }).ExecuteCommand(); db.Insertable(new RoomA() { RoomId = 6, RoomName = "清华003厅", SchoolId = 2 }).ExecuteCommand(); db.Insertable(new SchoolA() { SchoolId = 1, SchoolName = "北大" }).ExecuteCommand(); db.Insertable(new SchoolA() { SchoolId = 2, SchoolName = "清华" }).ExecuteCommand(); db.Insertable(new StudentA() { StudentId = 1, SchoolId = 1, Name = "北大jack" }).ExecuteCommand(); db.Insertable(new StudentA() { StudentId = 2, SchoolId = 1, Name = "北大tom" }).ExecuteCommand(); db.Insertable(new StudentA() { StudentId = 3, SchoolId = 2, Name = "清华jack" }).ExecuteCommand(); db.Insertable(new StudentA() { StudentId = 4, SchoolId = 2, Name = "清华tom" }).ExecuteCommand(); //先用Mapper导航映射查出第二层 var list = db.Queryable().Mapper(x => x.SchoolA, x => x.SchoolId).ToList(); //参数1 :将第二层对象合并成一个集合 参数2:委托 //说明:如果2级对象是集合用SelectMany db.ThenMapper(list.Select(it => it.SchoolA), sch => { //参数1: room表关联字段 参数2: school表关联字段, 参数3: school当前记录 sch.RoomList = db.Queryable().SetContext(room => room.SchoolId, () => sch.SchoolId, sch).ToList(); }); } public class StudentA { [SugarColumn(IsPrimaryKey = true)] public int StudentId { get; set; } public string Name { get; set; } public int SchoolId { get; set; } [SugarColumn(IsIgnore = true)] public SchoolA SchoolA { get; set; } } public class SchoolA { [SugarColumn(IsPrimaryKey = true)] public int SchoolId { get; set; } public string SchoolName { get; set; } [SugarColumn(IsIgnore = true)] public List RoomList { get; set; } } public class RoomA { [SugarColumn(IsPrimaryKey = true)] public int RoomId { get; set; } public string RoomName { get; set; } public int SchoolId { get; set; } } } }