转帖：PageSplit分页原理

1 --!定义存储过程
2  
3 ALTER PROCEDURE PageSplit
4 (
5   @PageCurrent int, --当前页
6   @PageCount int, --每页的数量
7   @PageTotal int output --总共有多少记录
8 )
9 AS
10     declare @Start int --当前页的第一行是总记录的第几行
11     declare @Last int  --当前页的最后一行是总记录的第几行
12    
13     set @Start=(@PageCurrent-1)*@PageCount+1
14     set @Last=@PageCurrent*@PageCount
15    
16     --得到总记录数
17     set @PageTotal=(select count(*) from NewsInfo)
18    
19     --查询的信息
20     select NewsTitle,NewsDate from NewsInfo where NewsID between @Start and @Last order by NewsDate desc
21    
22     RETURN

C#代码：

 1 public partial class News_PageSplit : System.Web.UI.Page
 2 {
 3     int PageCount = 5;
 4     
 5     protected void Page_Load(object sender, EventArgs e)
 6     {
 7         if (!Page.IsPostBack)
 8         {
 9             int PageCurrent =1;
10             
11             ShowMes(PageCurrent, PageCount);
12           
13         }
14     }
15     public void ShowMes(int pagecurrent,int pagecount)
16     {
17         SqlConnection Conn = new SqlConnection(System.Configuration.ConfigurationManager.AppSettings["PhotoConn"]);
18         Conn.Open();
19         SqlDataAdapter da =new SqlDataAdapter ("PageSplit",Conn);
20         da.SelectCommand.CommandType=CommandType.StoredProcedure;
21         //SqlParameter[] myparam ={  new SqlParameter("@PageCurrent",pagecurrent),
22         //                           new SqlParameter("@PageCount",pagecount)                          
23         //                        };
24        da.SelectCommand.Parameters.Add("@PageCurrent", pagecurrent);
25        da.SelectCommand.Parameters.Add("@pageCount",pagecount);
26        da.SelectCommand.Parameters.Add("@PageTotal",SqlDbType.Int);
27        da.SelectCommand.Parameters["@PageTotal"].Direction = ParameterDirection.Output;
28 
29         //绑定数据源
30 
31        DataSet ds = new DataSet();
32        da.Fill(ds);
33         //总记录数
34        double total = Convert.ToDouble(da.SelectCommand.Parameters["@PageTotal"].Value);
35         //总页数
36        double page = Math.Ceiling(total / PageCount);
37         //当前页
38        LabCurrent.Text = pagecurrent.ToString();
39        //总共有多少页
40        LabCount.Text = page.ToString();
41 
42        GridView1.DataSource = ds;
43        GridView1.DataBind();
44 
45        BindButton();
46     }
47     protected void LinkButton2_Click(object sender, EventArgs e)
48     {
49             int current = int.Parse(LabCurrent.Text) - 1;
50             LabCurrent.Text = current.ToString();
51             ShowMes(current, PageCount);
52       
53     }
54     protected void LinkButton1_Click(object sender, EventArgs e)
55     {
56             int current = int.Parse(LabCurrent.Text) + 1;
57             LabCurrent.Text = current.ToString();
58             ShowMes(current, PageCount);
59     }
60     public void BindButton()
61     {
62         if (LabCurrent.Text == "1")
63         {
64             LbPrev.Enabled = false;
65         }
66         else
67         {
68             LbPrev.Enabled = true;
69         }
70 
71         if (LabCurrent.Text == LabCount.Text)
72         {
73             LBnext.Enabled = false;
74         }
75         else
76         {
77             LBnext.Enabled = true;
78         }
79     }
80 }