linq存储过程返回多条结果集
曾经被linq存储过程返回多个结果所困扰,今晚加班,问题解决,分享一下思路:
linq默认生成的代码是ISingleResult的,也就是只能返回一条结果集,我们先动手脚,将其改成IMultipleResults 的.实体类根据不同情况更改.
更改前:
[Function(Name="dbo.MeterTaskStat")]
public ISingleResult<XXXX> MeterTaskStat([Parameter(Name="MeterTaskType", DbType="Int")] System.Nullable<int> meterTaskType, [Parameter(Name="StartDate", DbType="DateTime")] System.Nullable<System.DateTime> startDate, [Parameter(Name="EndDate", DbType="DateTime")] System.Nullable<System.DateTime> endDate)
{
IExecuteResult result = this.ExecuteMethodCall(this, ((MethodInfo)(MethodInfo.GetCurrentMethod())), meterTaskType, startDate, endDate);
return ((ISingleResult<XXXXXX>)(result.ReturnValue));
}
更改后:
[Function(Name="dbo.MeterTaskStat")]
[ResultType(typeof(TaskStatData))]
public IMultipleResults MeterTaskStat([Parameter(Name = "MeterTaskType", DbType = "Int")] System.Nullable<int> meterTaskType, [Parameter(Name = "StartDate", DbType = "DateTime")] System.Nullable<System.DateTime> startDate, [Parameter(Name = "EndDate", DbType = "DateTime")] System.Nullable<System.DateTime> endDate)
{
IExecuteResult result = this.ExecuteMethodCall(this, ((MethodInfo)(MethodInfo.GetCurrentMethod())), meterTaskType, startDate, endDate);
return ((IMultipleResults)(result.ReturnValue));
}
注意到 多一条: [ResultType(typeof(TaskStatData))] 的记录吧,简单介绍一下,必须得为存储过程的结果返回一个实体类型,而TaskStatData就是自己定义的类,[ResultType(typeof(TaskStatData))]必须加上,加存储过程返回值.
存储过程:
set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
go
-- ===================================================
-- Author: MaHong
-- Create date: 2008-09-11
-- Description: 根据口径统计某段时间内水表复装任务信息
-- ===================================================
ALTER PROCEDURE [dbo].[MeterTaskStat]
@MeterTaskType INT,
@StartDate DateTime,
@EndDate DateTime
AS
BEGIN
SET NOCOUNT ON;
SELECT MeterCaliberName,SUM(Requisition) AS RequisitionCount,SUM(Approve) AS ApproveCount,
SUM(Disapprove) AS DisapproveCount,SUM(WaitWork) AS WaitWorkCount,
SUM(CompleteY) AS CompleteYCount, SUM(CompleteN) AS CompleteNCount,
SUM(Requisition+Approve+Disapprove+WaitWork+CompleteY+CompleteN) AS Subtotal
FROM (SELECT MeterCaliberName
,CASE WHEN MeterTaskStatus=0 THEN 1 ELSE 0 END Requisition
,CASE WHEN MeterTaskStatus=1 THEN 1 ELSE 0 END Approve
,CASE WHEN MeterTaskStatus=11 THEN 1 ELSE 0 END Disapprove
,CASE WHEN MeterTaskStatus=2 THEN 1 ELSE 0 END WaitWork
,CASE WHEN MeterTaskStatus=4 THEN 1 ELSE 0 END CompleteY
,CASE WHEN MeterTaskStatus=5 THEN 1 ELSE 0 END CompleteN
FROM View_MeterTaskMaintain WHERE [MeterTaskType] = @MeterTaskType AND StartDate BETWEEN @StartDate AND @EndDate) tempTable
GROUP BY MeterCaliberName
END
然后在business中间层直接调用:
public class StatTaskControl : ControlBase
{
public IEnumerable<TaskStatData> GetStatInfo(TaskType type, DateTime startDate, DateTime endDate)
{
IMultipleResults info = Context.MeterTaskStat((int)type, startDate, endDate);
IEnumerable<TaskStatData> data = info.GetResult<TaskStatData>();
return data;
}
}
ui层获取:
protected void StatButton_Click(object sender, EventArgs e)
{
DateTime startDate = DateTime.Parse(StartDate.Text);
DateTime endDate = DateTime.Parse(EndDate.Text);
TaskType type = TaskType.Remove;
IEnumerable<TaskStatData> info = _control.GetStatInfo(type, startDate, endDate);
List<TaskStatData> data = info.ToList();
RemoveGridView.DataSource = data;
RemoveGridView.DataBind();
}
整个过程大概就是这么几步.也不是太困难!