Sqlserver存储过程和C#分页类简化你的代码!
Sqlserver存储过程和C#分页类简化你的代码! 下面是存储过程（sqlserver2000下通过)
--最通用的分页存储过程
-- 获取指定页的数据
CREATE PROCEDURE Pagination
@tblName varchar(255), -- 表名
@strGetFields varchar(1000) = '*', -- 需要返回的列
@fldName varchar(255)='', -- 排序的字段名
@PageSize int = 10, -- 页尺寸
@PageIndex int = 1, -- 页码
@doCount bit = 0, -- 返回记录总数, 非 0 值则返回
@OrderType bit = 0, -- 设置排序类型, 非 0 值则降序
@strWhere varchar(1500) = '' -- 查询条件 (注意: 不要加 where)
AS
declare @strSQL varchar(5000) -- 主语句
declare @strTmp varchar(110) -- 临时变量
declare @strOrder varchar(400) -- 排序类型
if @doCount != 0
begin
if @strWhere !=''
set @strSQL = 'select count(*) as Total from ['+ @tblName +'] where '+ @strWhere
else
set @strSQL = 'select count(*) as Total from ['+ @tblName +']'
end
--以上代码的意思是如果@doCount传递过来的不是0，就执行总数统计。以下的所有代码都
--是@doCount为0的情况
else
begin
if @OrderType != 0
begin
set @strTmp = '<(select min'
set @strOrder = ' order by ['+ @fldName +'] desc'
--如果@OrderType不是0，就执行降序，这句很重要！
end
else
begin
set @strTmp = '>(select max'
set @strOrder = ' order by ['+ @fldName +'] asc'
end
if @PageIndex = 1
begin
if @strWhere != ''
set @strSQL = 'select top ' + str(@PageSize) +' '+@strGetFields+ ' from ['+ @tblName +'] where ' + @strWhere + ' ' + @strOrder
else
set @strSQL = 'select top ' + str(@PageSize) +' '+@strGetFields+ ' from ['+ @tblName +'] '+ @strOrder
--如果是第一页就执行以上代码，这样会加快执行速度
end
else
begin
--以下代码赋予了@strSQL以真正执行的SQL代码
set @strSQL = 'select top ' + str(@PageSize) +' '+@strGetFields+ ' from [' + @tblName +'] where [' + @fldName + ']' + @strTmp + '(['+ @fldName + '])
from (select top ' + str((@PageIndex-1)*@PageSize) + ' ['+ @fldName + '] from ['+ @tblName +']' + @strOrder + ') as tblTmp)'+ @strOrder
if @strWhere != ''
set @strSQL = 'select top ' + str(@PageSize) +' '+@strGetFields+ ' from ['+ @tblName +'] where [' + @fldName + ']' + @strTmp + '(['+ @fldName + ']) from (select top ' + str((@PageIndex-1)*@PageSize) + ' ['+ @fldName + ']
from ['+ @tblName +'] where ' + @strWhere + ' ' + @strOrder + ') as tblTmp) and ' + @strWhere + ' ' + @strOrder
end
end
exec ( @strSQL)
GO
下面是C#的代码
using System.Data ;
using System.Data.SqlClient ;
using Microsoft.ApplicationBlocks.Data ;
using System.Web ;
using System.Web.UI ;
namespace RssLayer.PageHelper
{
/**//// <summary>
/// 分页类PagerHelper 的摘要说明。
/// </summary>
public class PagerHelper
{
private string connectionString;
public PagerHelper(string tblname,string sortname,bool docount,string connectionString)
{
this.tblName = tblname;
this.fldName = sortname ;
this.connectionString = connectionString ;
this.docount = docount;
}
public PagerHelper(string tblname,bool docount,
string strGetFields, string fldName,int pagesize,
int pageindex,bool ordertype,string strwhere,string connectionString
)
{
this.tblName = tblname ;
this.docount = docount ;
this.strGetFields = strGetFields ;
this.fldName = fldName;
this.pagesize = pagesize ;
this.pageindex = pageindex;
this.ordertype = ordertype ;
this.strwhere = strwhere ;
this.connectionString = connectionString ;
}
/**//// <summary>
/// 得到记录集的构造函数
/// </summary>
/// <param name="tblname"></param>
/// <param name="strwhere"></param>
/// <param name="connectionString"></param>
public PagerHelper(string tblname,string strwhere,string connectionString)
{
this.tblName = tblname;
this.strwhere = strwhere ;
this.docount = true;
this.connectionString = connectionString ;
}
private string tblName;
public string TblName
{
get{return tblName;}
set{tblName =value;}
}
private string strGetFields="*";
public string StrGetFields
{
get{return strGetFields ;}
set{strGetFields =value;}
}
private string fldName=string.Empty;
public string FldName
{
get{return fldName ;}
set{fldName =value;}
}
private int pagesize =10;
public int PageSize
{
get{return pagesize ;}
set{pagesize =value;}
}
private int pageindex =1;
public int PageIndex
{
get{return pageindex ;}
set{pageindex =value;}
}
private bool docount=false;
public bool DoCount
{
get{return docount ;}
set{docount =value;}
}
private bool ordertype=false;
public bool OrderType
{
get{return ordertype ;}
set{ordertype =value;}
}
private string strwhere=string.Empty ;
public string StrWhere
{
get{return strwhere ;}
set{strwhere =value;}
}
public IDataReader GetDataReader()
{
if(this.docount)
{
throw new ArgumentException("要返回记录集，DoCount属性一定为false");
}
// System.Web.HttpContext.Current.Response.Write(pageindex);
return SqlHelper.ExecuteReader(connectionString,CommandType.StoredProcedure,"Pagination",
new SqlParameter("@tblName",this.tblName),
new SqlParameter("@strGetFields",this.strGetFields),
new SqlParameter("@fldName",this.fldName),
new SqlParameter("@PageSize",this.pagesize),
new SqlParameter("@PageIndex",this.pageindex),
new SqlParameter("@doCount",this.docount),
new SqlParameter("@OrderType",this.ordertype),
new SqlParameter("@strWhere",this.strwhere)
);
}
public DataSet GetDataSet()
{
if(this.docount)
{
throw new ArgumentException("要返回记录集，DoCount属性一定为false");
}
return SqlHelper.ExecuteDataset(connectionString,CommandType.StoredProcedure,"Pagination",
new SqlParameter("@tblName",this.tblName),
new SqlParameter("@strGetFields",this.strGetFields),
new SqlParameter("@fldName",this.fldName),
new SqlParameter("@PageSize",this.pagesize),
new SqlParameter("@PageIndex",this.pageindex),
new SqlParameter("@doCount",this.docount),
new SqlParameter("@OrderType",this.ordertype),
new SqlParameter("@strWhere",this.strwhere)
);
}
public int GetCount()
{
if(!this.docount)
{
throw new ArgumentException("要返回总数统计，DoCount属性一定为true");
}
return (int)SqlHelper.ExecuteScalar(connectionString,CommandType.StoredProcedure,"Pagination",
new SqlParameter("@tblName",this.tblName),
new SqlParameter("@strGetFields",this.strGetFields),
new SqlParameter("@fldName",this.fldName),
new SqlParameter("@PageSize",this.pagesize),
new SqlParameter("@PageIndex",this.pageindex),
new SqlParameter("@doCount",this.docount),
new SqlParameter("@OrderType",this.ordertype),
new SqlParameter("@strWhere",this.strwhere)
);
}
}
}
如何调用？？？
假如我已经建立了2个类。一个是FavList数据库实体类，一个FavListCollection集合类。FavListCollection存储了FavList实体类的集合。
我可以这样写一个方法。
/**//// <summary>
/// 返回FavList集合,使用存储过程自定义分页。
/// </summary>
/// <param name="userid">数据库FavList的字段，用户ID</param>
/// <param name="strwhere">查找的条件</param>
/// <param name="ordertype">排序，true表示Desc,false表示asc</param>
/// <param name="fldname">排序的字段，只能是一个字段</param>
/// <param name="pagesize">每页的记录数</param>
/// <param name="pageindex">到第几页的参数，由1开始。1表示第一页，以此类推。</param>
/// <param name="recordcount">总记录数。</param>
/// <returns></returns>
public override FavListCollection GetFavListsByUser(int userid, string strwhere,
bool ordertype, string fldname, int pagesize,
int pageindex,out int recordcount
)
{
recordcount = 0;
PagerHelper helper = new PagerHelper("Vfavlist",strwhere,ConnectionString); //VFavList是View
recordcount = helper.GetCount();
PagerHelper helper2 = new PagerHelper("Vfavlist",false," * ",fldname,
pagesize,pageindex,ordertype,strwhere,ConnectionString);
IDataReader dr = helper2.GetDataReader();
FavListCollection list = new FavListCollection();
while(dr.Read())
{
list.Add(PopulateFavList(dr));
}
dr.Close();
return list;
}
DataGrid调用就不用说了吧。。
关于该分页的Bug和局限性
Bug：当排序那个字段内容相同的时候（例如：按时间来排序，而时间是一样的话。后面的记录会显示不出来。本人测试过)
局限性：排序只能一个字段，不能超过一个
