话说 C# 程序员人手一个 ORM
dotNET全栈开发
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·
2022-11-25 00:15
支持Oracle、MSSQL、MySQL、SQLite四种数据库
方便扩展以支持更多关系数据库
有配套的Model生成器
insert、update、delete操作无需写SQL
查询使用原生SQL
查询结果通过映射转成实体类或实体类集合
支持参数化查询，通过SqlString类提供非常方便的参数化查询
支持连接多个数据源
单表查询、单表分页查询、简单的联表分页查询支持Lambda表达式
支持原生SQL和Lambda表达式
代码实现比较简单，有经验的程序员容易掌控代码，自己修改和扩展
查询使用原生SQL
联表查询对Lambda表达式的支持比较弱
复杂查询不支持Lambda表达式
单表查询可以使用Lambda表达式
联表查询以及复杂查询建议使用原生SQL或原生SQL和Lambda表达式混写
public class DBHelper
{
#region 变量
private static ISessionHelper _sessionHelper = new SessionHelper(ConfigurationManager.ConnectionStrings["DefaultConnection"].ToString(), DBType.MySQL);
#endregion
#region 获取 ISession
/// <summary>
/// 获取 ISession
/// </summary>
public static ISession GetSession()
{
return _sessionHelper.GetSession();
}
#endregion
#region 获取 ISession (异步)
/// <summary>
/// 获取 ISession (异步)
/// </summary>
public static async Task<ISession> GetSessionAsync()
{
return await _sessionHelper.GetSessionAsync();
}
#endregion
}
使用Model生成器生成实体类
实体类放在Models文件夹中 扩展实体类放在ExtModels文件夹中 实体类和扩展实体类使用partial修饰，实际上是一个类，放在不同的文件中 如果需要添加自定义属性，请修改ExtModels，不要修改Models
实体类示例
/// <summary>
/// 订单表
/// </summary>
[Serializable]
[DBTable("bs_order")]
public partial class BsOrder
{
/// <summary>
/// 主键
/// </summary>
[DBKey]
[DBField]
public string Id { get; set; }
/// <summary>
/// 订单时间
/// </summary>
[DBField("order_time")]
public DateTime OrderTime { get; set; }
/// <summary>
/// 订单金额
/// </summary>
[DBField]
public decimal? Amount { get; set; }
/// <summary>
/// 下单用户
/// </summary>
[DBField("order_userid")]
public long OrderUserid { get; set; }
/// <summary>
/// 订单状态(0草稿 1已下单 2已付款 3已发货 4完成)
/// </summary>
[DBField]
public int Status { get; set; }
/// <summary>
/// 备注
/// </summary>
[DBField]
public string Remark { get; set; }
/// <summary>
/// 创建者ID
/// </summary>
[DBField("create_userid")]
public string CreateUserid { get; set; }
/// <summary>
/// 创建时间
/// </summary>
[DBField("create_time")]
public DateTime CreateTime { get; set; }
/// <summary>
/// 更新者ID
/// </summary>
[DBField("update_userid")]
public string UpdateUserid { get; set; }
/// <summary>
/// 更新时间
/// </summary>
[DBField("update_time")]
public DateTime? UpdateTime { get; set; }
}
修改扩展实体类
修改扩展实体类，添加自定义属性 下面的扩展实体类中，查询时OrderUserRealName会被自动填充，查询SQL：select t.*, u.real_name as OrderUserRealName from ...... DetailList不会被自动填充，需要手动查询
扩展实体类示例
/// <summary>
/// 订单表
/// </summary>
public partial class BsOrder
{
/// <summary>
/// 订单明细集合
/// </summary>
public List<BsOrderDetail> DetailList { get; set; }
/// <summary>
/// 下单用户姓名
/// </summary>
public string OrderUserRealName { get; set; }
/// <summary>
/// 下单用户名
/// </summary>
public string OrderUserName { get; set; }
}
添加
public void Insert(SysUser info)
{
using (var session = DBHelper.GetSession())
{
session.Insert(info);
}
}
批量添加
public void Insert(List<SysUser> list)
{
using (var session = DBHelper.GetSession())
{
session.Insert(list);
}
}
修改
public void Update(SysUser info)
{
using (var session = DBHelper.GetSession())
{
session.Update(info);
}
}
批量修改
public void Update(List<SysUser> list)
{
using (var session = DBHelper.GetSession())
{
session.Update(list);
}
}
删除
public void Delete(string id)
{
using (var session = DBHelper.GetSession())
{
session.DeleteById<SysUser>(id);
}
}
条件删除
using (var session = DBHelper.GetSession())
{
session.DeleteByCondition<SysUser>(string.Format("id>=12"));
}
查询单个记录
public SysUser Get(string id)
{
using (var session = DBHelper.GetSession())
{
return session.FindById<SysUser>(id);
}
}
using (var session = DBHelper.GetSession())
{
return session.FindBySql<SysUser>("select * from sys_user");
}
简单查询
using (var session = DBHelper.GetSession())
{
string sql = "select * from CARINFO_MERGE";
List<CarinfoMerge> result = session.FindListBySql<CarinfoMerge>(sql);
}
条件查询
public List<BsOrder> GetList(int? status, string remark, DateTime? startTime, DateTime? endTime)
{
using (var session = DBHelper.GetSession())
{
SqlString sql = session.CreateSqlString(@"
select t.*, u.real_name as OrderUserRealName
from bs_order t
left join sys_user u on t.order_userid=u.id
where 1=1");
sql.AppendIf(status.HasValue, " and t.status=@status", status);
sql.AppendIf(!string.IsNullOrWhiteSpace(remark), " and t.remark like concat('%',@remark,'%')", remark);
sql.AppendIf(startTime.HasValue, " and t.order_time>=STR_TO_DATE(@startTime, '%Y-%m-%d %H:%i:%s') ", startTime.Value.ToString("yyyy-MM-dd HH:mm:ss"));
sql.AppendIf(endTime.HasValue, " and t.order_time<=STR_TO_DATE(@endTime, '%Y-%m-%d %H:%i:%s') ", endTime.Value.ToString("yyyy-MM-dd HH:mm:ss"));
sql.Append(" order by t.order_time desc, t.id asc ");
List<BsOrder> list = session.FindListBySql<BsOrder>(sql.SQL, sql.Params);
return list;
}
}
分页查询
public List<BsOrder> GetListPage(ref PageModel pageModel, int? status, string remark, DateTime? startTime, DateTime? endTime)
{
using (var session = DBHelper.GetSession())
{
SqlString sql = session.CreateSqlString(@"
select t.*, u.real_name as OrderUserRealName
from bs_order t
left join sys_user u on t.order_userid=u.id
where 1=1");
sql.AppendIf(status.HasValue, " and t.status=@status", status);
sql.AppendIf(!string.IsNullOrWhiteSpace(remark), " and t.remark like concat('%',@remark,'%')", remark);
sql.AppendIf(startTime.HasValue, " and t.order_time>=STR_TO_DATE(@startTime, '%Y-%m-%d %H:%i:%s') ", startTime.Value.ToString("yyyy-MM-dd HH:mm:ss"));
sql.AppendIf(endTime.HasValue, " and t.order_time<=STR_TO_DATE(@endTime, '%Y-%m-%d %H:%i:%s') ", endTime.Value.ToString("yyyy-MM-dd HH:mm:ss"));
string orderby = " order by t.order_time desc, t.id asc ";
pageModel = session.FindPageBySql<BsOrder>(sql.SQL, orderby, pageModel.PageSize, pageModel.CurrentPage, sql.Params);
return pageModel.GetResult<BsOrder>();
}
}
事务
public string Insert(BsOrder order, List<BsOrderDetail> detailList)
{
using (var session = DBHelper.GetSession())
{
try
{
session.BeginTransaction();
order.Id = Guid.NewGuid().ToString("N");
order.CreateTime = DateTime.Now;
decimal amount = 0;
foreach (BsOrderDetail detail in detailList)
{
detail.Id = Guid.NewGuid().ToString("N");
detail.OrderId = order.Id;
detail.CreateTime = DateTime.Now;
amount += detail.Price * detail.Quantity;
session.Insert(detail);
}
order.Amount = amount;
session.Insert(order);
session.CommitTransaction();
return order.Id;
}
catch (Exception ex)
{
session.RollbackTransaction();
Console.WriteLine(ex.Message + "\r\n" + ex.StackTrace);
throw ex;
}
}
}
异步查询
public async Task<List<BsOrder>> GetListPageAsync(PageModel pageModel, int? status, string remark, DateTime? startTime, DateTime? endTime)
{
using (var session = await DBHelper.GetSessionAsync())
{
SqlString sql = session.CreateSqlString(@"
select t.*, u.real_name as OrderUserRealName
from bs_order t
left join sys_user u on t.order_userid=u.id
where 1=1");
sql.AppendIf(status.HasValue, " and t.status=@status", status);
sql.AppendIf(!string.IsNullOrWhiteSpace(remark), " and t.remark like concat('%',@remark,'%')", remark);
sql.AppendIf(startTime.HasValue, " and t.order_time>=STR_TO_DATE(@startTime, '%Y-%m-%d %H:%i:%s') ", startTime.Value.ToString("yyyy-MM-dd HH:mm:ss"));
sql.AppendIf(endTime.HasValue, " and t.order_time<=STR_TO_DATE(@endTime, '%Y-%m-%d %H:%i:%s') ", endTime.Value.ToString("yyyy-MM-dd HH:mm:ss"));
string orderby = " order by t.order_time desc, t.id asc ";
pageModel = await session.FindPageBySqlAsync<BsOrder>(sql.SQL, orderby, pageModel.PageSize, pageModel.CurrentPage, sql.Params);
return pageModel.GetResult<BsOrder>();
}
}
条件查询(使用 ForContains、ForStartsWith、ForEndsWith、ForDateTime、ForList 等辅助方法)
public List<BsOrder> GetListExt(int? status, string remark, DateTime? startTime, DateTime? endTime, string ids)
{
using (var session = DBHelper.GetSession())
{
SqlString sql = session.CreateSqlString(@"
select t.*, u.real_name as OrderUserRealName
from bs_order t
left join sys_user u on t.order_userid=u.id
where 1=1");
sql.AppendIf(status.HasValue, " and t.status=@status", status);
sql.AppendIf(!string.IsNullOrWhiteSpace(remark), " and t.remark like @remark", sql.ForContains(remark));
sql.AppendIf(startTime.HasValue, " and t.order_time >= @startTime ", sql.ForDateTime(startTime.Value));
sql.AppendIf(endTime.HasValue, " and t.order_time <= @endTime ", sql.ForDateTime(endTime.Value));
sql.Append(" and t.id in @ids ", sql.ForList(ids.Split(',').ToList()));
sql.Append(" order by t.order_time desc, t.id asc ");
List<BsOrder> list = session.FindListBySql<BsOrder>(sql.SQL, sql.Params);
return list;
}
}
使用Lambda表达式单表查询
单表分页查询使用ToPageList替换ToList即可
public void TestQueryByLambda6()
{
using (var session = DBHelper.GetSession())
{
SqlString<BsOrder> sql = session.CreateSqlString<BsOrder>();
string remark = "测试";
List<BsOrder> list = sql.Query()
.WhereIf(!string.IsNullOrWhiteSpace(remark),
t => t.Remark.Contains(remark)
&& t.CreateTime < DateTime.Now
&& t.CreateUserid == "10")
.OrderByDescending(t => t.OrderTime).OrderBy(t => t.Id)
.ToList();
foreach (BsOrder item in list)
{
Console.WriteLine(ModelToStringUtil.ToString(item));
}
}
}
使用Lambda表达式联表分页查询(简单的联表查询，复杂情况请使用原生SQL或原生SQL和Lambda表达式混写)
public void TestQueryByLambda7()
{
using (var session = DBHelper.GetSession())
{
SqlString<BsOrder> sql = session.CreateSqlString<BsOrder>();
int total;
List<string> idsNotIn = new List<string>() { "100007", "100008", "100009" };
List<BsOrder> list = sql.Query()
.Select<SysUser>(u => u.UserName, t => t.OrderUserName)
.Select<SysUser>(u => u.RealName, t => t.OrderUserRealName)
.LeftJoin<SysUser>((t, u) => t.OrderUserid == u.Id)
.LeftJoin<BsOrderDetail>((t, d) => t.Id == d.OrderId)
.Where<SysUser, BsOrderDetail>((t, u, d) => t.Remark.Contains("订单") && u.CreateUserid == "1" && d.GoodsName != null)
.WhereIf<BsOrder>(true, t => t.Remark.Contains("测试"))
.WhereIf<BsOrder>(true, t => !idsNotIn.Contains(t.Id))
.WhereIf<SysUser>(true, u => u.CreateUserid == "1")
.OrderByDescending(t => t.OrderTime).OrderBy(t => t.Id)
.ToPageList(1, 20, out total);
foreach (BsOrder item in list)
{
Console.WriteLine(ModelToStringUtil.ToString(item));
}
}
}
原生SQL和Lambda表达式混写
public void TestQueryByLambda9()
{
using (var session = DBHelper.GetSession())
{
SqlString<BsOrder> sql = session.CreateSqlString<BsOrder>(@"
select t.*, u.real_name as OrderUserRealName
from bs_order t
left join sys_user u on t.order_userid=u.id
where 1=1");
List<BsOrder> list = sql.Where(t => t.Status == int.Parse("0")
&& t.Status == new BsOrder().Status
&& t.Remark.Contains("订单")
&& t.Remark != null
&& t.OrderTime >= new DateTime(2010, 1, 1)
&& t.OrderTime <= DateTime.Now.AddDays(1))
.WhereIf<SysUser>(true, u => u.CreateTime < DateTime.Now)
.OrderByDescending(t => t.OrderTime).OrderBy(t => t.Id)
.ToList();
foreach (BsOrder item in list)
{
Console.WriteLine(ModelToStringUtil.ToString(item));
}
}
}评论