using System;
using System.Collections.Specialized;
namespace web
{
/// <summary>
/// MultiOrderPagerSQL 的摘要说明
/// </summary>
public class MultiOrderPagerSQL
{
private NameValueCollection orders = new NameValueCollection();
private string table_;
private string where_="";//1=1 and 2=2 的格式
private string outfields_;
private int nowPageIndex_=0;
private int pagesize_=0;
private string sql_;//要返回的SQL
public MultiOrderPagerSQL()
{
}
/****************方法*******************/
public void addOrderField(string field, string direction)
{
orders.Add(field, direction);
}
public string getSQL()
{
//排序字段
string orderList="";//用户期望的排序
string orderList2 = "";//对用户期望的排序的反排序
string orderList3 = "";//用户期望的排序,去掉了前缀.复合查询里的外层的排序不能是类似这样的table1.id,要去掉table1.。
if (orders.Count > 0)
{
string[] str = orders.AllKeys;
foreach (string s in str)
{
string direction="asc";//默认一个方向
if (orders[s].ToString() == "asc")
direction = "desc";
//去掉前缀的字段名称
string s2 = "";
int index = s.IndexOf(".") + 1;
s2 = s.Substring(index);
orderList =orderList + s +" "+ orders[s] +",";
orderList2 = orderList2 + s2 + " " + direction + ",";
orderList3 = orderList3 + s2 + " " + orders[s] + ",";
}
//去掉最后的,号
orderList = orderList.Substring(0,orderList.Length-1);
orderList2 = orderList2.Substring(0, orderList2.Length - 1);
orderList3 = orderList3.Substring(0, orderList3.Length - 1);
}
//return orderList2;
//形成SQL
string strTemp;
strTemp = "select * from \n ( select top {7} * from ( select top {6} {0} from {1} \n";
if (where_ != "")
strTemp = strTemp + " where {2} \n";
if(orderList!="")
strTemp = strTemp + " order by {3} ) as tmp order by {4} \n ) \n as tmp2 \n order by {5} \n";
strTemp = string.Format(strTemp, outfields_, table_, where_, orderList, orderList2, orderList3, nowPageIndex_ * pagesize_, pagesize_);
return strTemp;
}
/****************属性*******************/
public string table
{
set { table_ = value; }
}
public string where
{
set { where_ = value; }
}
public string outfields
{
set { outfields_ = value; }
}
public int nowPageIndex
{
set { nowPageIndex_ = value; }
}
public int pagesize
{
set { pagesize_ = value; }
}
}
}

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class MultiOrderPagerSQLTest : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
web.MultiOrderPagerSQL sql = new web.MultiOrderPagerSQL();
//sql.addOrderField("t1.id", "desc");//第一排序字段
sql.addOrderField("t1.hits", "desc");//第二排序字段
sql.table = "joke t1,type t2";
sql.outfields = "t1.*,t2.type";
sql.nowPageIndex = 5;
sql.pagesize = 10;
sql.where = "t1.typeid=t2.typeid";
Response.Write(sql.getSQL());
}
}