在存储过程中实现分页.
我不是一个很有经验的程序员,在做项目的过程中会遇到很多的问题,在数据库中使用分页就是我做项目中遇到的一个问题.我从网上查了很多资料,有很多种方法.但我觉的创建临时数据表是最简单的方法,在我做Membership扩展时发现原来微软也是这样用的,你可一随便打开一个Membership的存储过程看看.
说了再多也没用,只要看看代码就清楚了,呵呵.
SqlHelper类:简化数据库查询类.
GetSimpleEntity(SqlDataReader reader):由于经常在项目中会用到好基础实体类的获取,所以单独写一个私有函数,以便重用;
值得注意的是获取总的记录数时可能类型为DbNull而导致错误.
第一次写,希望批评指正.
说了再多也没用,只要看看代码就清楚了,呵呵.
1
CREATE PROCEDURE dbo.CreateSimple
2
(
3
@PageIndex int,
4
@PageSize int
5
)
6
AS
7
BEGIN
8
--定义三个变量:
9
-- @PageLowerBound :所取出记录的下限.
10
-- @PageUpperBound: 所要取出记录的上限.
11
-- @TotalRecords: 返回记录总数,主要用于页面的计算.
12
DECLARE @PageLowerBound int
13
DECLARE @PageUpperBound int
14
DECLARE @TotalRecords int
15
16
--计算上下限的值.
17
SET @PageLowerBound=@PageIndex * @PageSize
18
SET @PageUpperBound=@PageLowerBound+@PageSize-1
19
20
--创建临时表:
21
--IndexId是标识,自动增长1;
22
--SimpleId由数据表[Simple]填充;
23
CREATE TABLE #PageIndexForSimple
24
(
25
IndexId int identity(1,1) NOT NULL,
26
SimpleId int
27
)
28
--填充临时表
29
INSERT INTO #PageIndexForSimple(SimpleId)
30
SELECT s.[SimpleId]
31
FROM [Simple] s
32
--这里可以加WHERE condition和ODER BY语句
33
34
--取得记录总数,其实影响行数就是记录总数
35
SELECT @TotalRecords=@@ROWCOUNT
36
37
--获取我们所要的记录.
38
SELECT s.*
39
FROM [Simple] s,#PageIndexForSimple p
40
WHERE s.[SimpleId]=p.[SimpleId]
41
AND p.[IndexId]>=@PageLowerBound
42
AND P.[IndexId]<=@PageUpperBound
43
ORDER BY s.[Simple]
44
45
--返回记录总数.
46
RETURE @TotalRecords
47
END
由上面的注释就能看懂了,呵呵,既然写到这里也把程序的代码写出来:
2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

1
Public List<Simple> GetSimple(int pageIndex,int pageIndex,out int totalRecords){
2
List<Simple> entity=new List<Simple>();
3
SqlParameter[]param=new SqlParameter[]{
4
new SqlParameter("@PageIndex",SqlDbType.Int),
5
new SqlParameter("@PageSize",SqlDbType.Int),
6
new SqlParameter("@ReturnValue",SqlDbType.Int),
7
};
8
param[0].Value=pageIndex;
9
param[1].Value=pageSize;
10
param[2].Direction = ParameterDirection.ReturnValue;
11
SqlDataReader reader=SqlHelper.ExecuteReader(CommandType.StoredProcedure, "GetSimple", param);
12
While(reader.Read()){
13
entity.Add(GetSimpleEntity(reader))
14
}
15
reader.Close();
16
try{
17
totalRecords=(int)param[2].Value;
18
}catch{}
19
return entity;
20
}
上面的一些函数是自己写的:
2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

SqlHelper类:简化数据库查询类.
GetSimpleEntity(SqlDataReader reader):由于经常在项目中会用到好基础实体类的获取,所以单独写一个私有函数,以便重用;
值得注意的是获取总的记录数时可能类型为DbNull而导致错误.
第一次写,希望批评指正.
【推荐】编程新体验,更懂你的AI,立即体验豆包MarsCode编程助手
【推荐】凌霞软件回馈社区,博客园 & 1Panel & Halo 联合会员上线
【推荐】抖音旗下AI助手豆包,你的智能百科全书,全免费不限次数
【推荐】博客园社区专享云产品让利特惠,阿里云新客6.5折上折
【推荐】轻量又高性能的 SSH 工具 IShell:AI 加持,快人一步