ASP.Net教程 ASP源码 关于ACCESS快速分页的补充!

前天看了编datagrid access分页的文章,很不错,但只提到用主键分页,本人整理了一下,写了个通用的分页方法,大家可以参考一下,有什么问题请指出,如下:
public class FastPageSql
{
private int allCount; //表中记录总数
private bool isDesc; //排序方式
private string primaryKey; //表的主键
private string orderKey; //排序键
private string selectFields; //要选择的字段
private string queryCondition; //筛选条件
private string tableName; //表名称
private int perPageCount; //每页显示数
private int pageIndex; //显示页的索引
private int totalIndex; //总页数
private int middleIndex; //中间页数;
public FastPageSql(int allcount,bool isdesc,string primarykey,string orderkey,string tablename,int perpagecount,int pageindex,string selectfields,string querycondition)
{
allCount=allcount;
isDesc=isdesc;
primaryKey=primarykey;
orderKey=orderkey;
selectFields=selectfields;
queryCondition=querycondition;
tableName=tablename;
perPageCount=perpagecount;
pageIndex=pageindex;
totalIndex=getTotalIndex();
middleIndex=(int)(totalIndex/2);
}
private int getTotalIndex()
{
if(allCount%perPageCount>0)
return (int)(allCount/perPageCount) 1;
else
return allCount/perPageCount;
}
public string GetFastPageSql()
{
string sql="";
if(pageIndex<=1)
{
#region 第一页代码
sql="select top " perPageCount " " selectFields " from " tableName " " ((queryCondition!="")?"where " queryCondition "":"") " order by " orderKey " " ((isDesc)?"desc":"asc") "";
#endregion
}
else if(1
{
#region 中间页之前
if(primaryKey==orderKey)
sql="select top " perPageCount " " selectFields " from " tableName " where " primaryKey "" ((isDesc)?"<":">") "(select " ((isDesc)?"min":"max") "(" primaryKey ") from(select top " perPageCount*(pageIndex-1) " " primaryKey " from " tableName " " ((queryCondition!="")?"where " queryCondition "":"") " order by " orderKey " " ((isDesc)?"desc":"asc") " )) " ((queryCondition!="")?"and " queryCondition "":"") " order by " orderKey " " ((isDesc)?"desc":"asc") "";
else
sql="select " selectFields " from (select top " perPageCount " " selectFields " from (select top " perPageCount*pageIndex " " selectFields " from " tableName " " ((queryCondition!="")?"where " queryCondition "":"") " order by " orderKey " " ((isDesc)?"desc":"asc") ") order by " orderKey " " ((isDesc)?"asc":"desc") ") order by " orderKey " " ((isDesc)?"desc":"asc") "";
#endregion
}
else if(middleIndex
#region 中间页到最后页之间
if(primaryKey==orderKey)
sql="select " selectFields " from (select top " perPageCount " " selectFields " from " tableName " where " primaryKey "" ((isDesc)?">":"<") "(select " ((isDesc)?"max":"min") "(" primaryKey ") from (select top " (allCount-perPageCount*pageIndex) " " primaryKey " from " tableName " " ((queryCondition!="")?"where " queryCondition "":"") " order by " orderKey " " ((isDesc)?"asc":"desc") " )) " ((queryCondition!="")?"and " queryCondition "":"") " order by " orderKey " " ((isDesc)?"asc":"desc") ") order by " orderKey " " ((isDesc)?"desc":"asc") "";
else
sql="select top " perPageCount " " selectFields " from (select top " (allCount-(pageIndex-1)*perPageCount) " " selectFields " from " tableName " " ((queryCondition!="")?"where " queryCondition "":"") " order by " orderKey " " ((isDesc)?"asc":"desc") ") order by " orderKey " " ((isDesc)?"desc":"asc") "";
#endregion
}
else if(pageIndex>=totalIndex)
{
#region 最后页
sql="select " selectFields " from (select top " (allCount-(totalIndex-1)*perPageCount) " " selectFields " from " tableName " " ((queryCondition!="")?"where " queryCondition "":"") " order by " orderKey " " ((isDesc)?"asc":"desc") ") order by " orderKey " " ((isDesc)?"desc":"asc") "";
#endregion
}
return sql;
}
}
返回的sql语句将只选择当前页所需要的记录,程序中直接填充到DataSet中显示即可!