Sql server存储过程和C#分页类简化你的代码

1/18/2006来源:C#应用人气:18737

Sqlserver存储过程和C#分页类简化你的代码!
在最近的项目中,由于要用到自定义分页的功能,本人就在网上找了个存储过程。结合C#写了个分页类。由于本人第一次写文章。写得不好,大家不要扔鸡蛋。。

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

出处:BLOG永不言拜