Repeater綁定數(shù)據(jù)庫，使用aspNetPager進(jìn)行分頁

　　分頁是Web中經(jīng)常遇到的功能，分頁主要有真分頁和假分頁。

　　所謂真分頁是指：每一頁顯示多少數(shù)據(jù)，就從數(shù)據(jù)庫讀多少數(shù)據(jù)；

　　假分頁是指：一次性從數(shù)據(jù)庫讀取所有數(shù)據(jù)，然后再進(jìn)行分頁。

這兩種分頁方式區(qū)別在于從數(shù)據(jù)庫讀取信息的方式，真分頁的效率高。假分頁在首次頁面加載的時候會比較慢（如果數(shù)據(jù)量較多）。

　　下面學(xué)習(xí)下使用AspNetPager進(jìn)行真分頁

1.前臺編寫Repeater所呈現(xiàn)的數(shù)據(jù)：

   <table width="650" border="1">    <tr>        <td class="tr1">            <asp:Label Text="姓名" runat="server"></asp:Label>        </td>        <td class="tr2">            <asp:Label Text="所在公司" runat="server"></asp:Label>        </td>        <td class="tr3">            <asp:Label Text="注冊ID" runat="server"></asp:Label>        </td>    </tr>    </table>    <asp:Repeater ID="Repeater1" runat="server">    <ItemTemplate>    <table border="1" width="650">    <tr>    <td class="tr1">    <%#Eval("E_Id")%>    </td>    <td class="tr2">    <%#Eval("C_Id") %>    </td>    <td class="tr3">    <%#Eval("User_Id") %>    </td>    </tr>    </table>    </ItemTemplate>    </asp:Repeater>                 

2.加入AspNetPager控件

    <webdiyer:AspNetPager ID="AspNetPager1" runat="server"         AlwaysShow="true" //始終顯示分頁控件，即使至分成一頁        UrlPaging="true"    //通過URL傳遞分頁信息          NumericButtonTextFormatString="[{0}]" //索引格式        ShowCustomInfoSection="Left"     //顯示當(dāng)前頁和總頁數(shù)信息，默認(rèn)值不顯示，為left則將顯示在頁索引前，為right則為頁索引后          ShowInputBox="Always"    //輸入框        TextAfterInputBox="頁"    //輸入框之后        TextBeforeInputBox="跳轉(zhuǎn)到第" >   //輸入框之前    </webdiyer:AspNetPager>        

3.后臺分頁及綁定數(shù)據(jù)

    PRotected void Page_Load(object sender, EventArgs e)        {            if (!IsPostBack)            {                BindRepeater();            }        }

a.BindRepeater()函數(shù)，綁定數(shù)據(jù)庫等操作

        public void BindRepeater()        {            this.AspNetPager1.PageSize = 5;//分頁大小            int count = 1;//當(dāng)前頁默認(rèn)為1            if (Request.QueryString["page"] != null)//如果當(dāng)前頁非空，則將URL中的page賦值為當(dāng)前頁的值            {                    count = Convert.ToInt32(Request.QueryString["page"].ToString());//使用URL傳遞分頁信息，（如果使用AspNetPager的PageChanged函數(shù)，會在函數(shù)中調(diào)用兩次PageChanged函數(shù)，影響運(yùn)行效率）            }                int num = (count - 1) * this.AspNetPager1.PageSize;  //當(dāng)前頁減1，乘以每頁顯示數(shù)目，得到前幾頁的數(shù)據(jù)數(shù)量                string sql = "select top " + this.AspNetPager1.PageSize + " * from Emp  where E_Id not in (" +                    " select top " + num + " E_Id from Emp order by  E_Id  asc) order by E_Id asc";//自定義的SQL語句，查找當(dāng)前頁的數(shù)據(jù)                            int recordcount;                DataSet ds = GetPage(sql, this.AspNetPager1.CurrentPageIndex, this.AspNetPager1.PageSize, out recordcount);                this.AspNetPager1.RecordCount = recordcount;                Repeater1.DataSource = ds;                Repeater1.DataBind();                AspNetPager1.CustomInfoHTML = "記錄總數(shù)：<b>" + AspNetPager1.RecordCount.ToString() + "</b>";                AspNetPager1.CustomInfoHTML += " 總頁數(shù)：<b>" + AspNetPager1.PageCount.ToString() + "</b>";                AspNetPager1.CustomInfoHTML += " 當(dāng)前頁：<font color=/"red/"><b>" + count + "</b></font>";                    }

b.GetPage函數(shù)，返回數(shù)據(jù)集

        /// <summary>        /// 獲得數(shù)據(jù)源        /// </summary>        /// <param name="sql">sql語句</param>        /// <param name="currentPage">當(dāng)前頁</param>        /// <param name="pagesize">分頁大小</param>        /// <param name="recordcount">總頁數(shù)</param>        /// <returns>DataSet</returns>        public DataSet GetPage(string sql, int currentPage, int pagesize, out int recordcount)        {           // String strSql = "select * from Emp";            SqlDataAdapter ada = new SqlDataAdapter(sql, GetConnection());            DataSet ds = new DataSet();            //int startRow = (currentPage - 1) * pagesize;            //ada.Fill(ds, startRow, pagesize, "table");//對讀取到的數(shù)據(jù)進(jìn)行分頁，假分頁時可以這樣操作            ada.Fill(ds, "table"); //填充            recordcount = GetPageRecord();//得到總頁數(shù)            return ds;        }       

c.GetPagRecord函數(shù)，獲得總記錄數(shù)

 /// <summary>        /// 獲得總記錄數(shù)        /// </summary>        /// <param name="sql"></param>        /// <returns></returns>        public int GetPageRecord()        {            String sql = "select count(*) from Emp";            SqlCommand cmd = new SqlCommand(sql, GetConnection());            cmd.Connection.Open();            int recordcount = (int)cmd.ExecuteScalar();            return recordcount;        }

d.GetConnection，獲得連接串

        public SqlConnection GetConnection()        {            SqlConnection conn = new SqlConnection("server=.;database=ComInfo;integrated security=true");            return conn;        }